/* ===== LANGUAGE TOGGLE ===== */
body.lang-ja .en {
  display: none !important;
}

body.lang-en .ja {
  display: none !important;
}

.lang-toggle {
  background: transparent;
  border: none;
  color: var(--text-dim);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  font-family: 'Outfit', sans-serif;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: color 0.2s;
  margin-right: 8px;
  letter-spacing: 0.03em;
}

.lang-toggle:hover {
  color: var(--text);
}

.lang-icon {
  font-size: 0.85rem;
  vertical-align: -0.05em;
}

/* ===== RESET & BASE ===== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0a0a0f;
  --bg-card: #16161f;
  --bg-dark: #08080d;
  --text: #e8e6e3;
  --text-dim: #9a9a9a;
  --accent: #f5a623;
  --accent2: #e8433e;
  --accent3: #4ecdc4;
  --accent4: #a78bfa;
  --border: rgba(255, 255, 255, 0.1);
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.5);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.accent {
  color: var(--accent);
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s;
}

a:hover {
  color: var(--accent3);
}

/* ===== HEADER ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 1.3rem;
  color: var(--text);
}

.logo:hover {
  color: var(--text);
}

.logo-icon {
  font-size: 1.6rem;
  color: var(--accent);
}

.nav {
  display: flex;
  gap: 28px;
}

.nav a {
  color: var(--text-dim);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  position: relative;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s;
}

.nav a:hover {
  color: var(--text);
}

.nav a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: 0.3s;
}

/* ===== HERO ===== */
@keyframes hero-fade-up {
  from {
    opacity: 0;
    transform: translateY(36px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes orb-drift-1 {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  40% {
    transform: translate(6%, -10%) scale(1.18);
  }

  70% {
    transform: translate(-4%, 7%) scale(0.9);
  }
}

@keyframes orb-drift-2 {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  35% {
    transform: translate(-7%, 6%) scale(1.12);
  }

  68% {
    transform: translate(5%, -5%) scale(1.2);
  }
}

@keyframes orb-drift-3 {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  50% {
    transform: translate(4%, -8%) scale(1.14);
  }
}

@keyframes string-shimmer {

  0%,
  100% {
    opacity: 0.07;
    box-shadow: none;
  }

  50% {
    opacity: 0.65;
    box-shadow: 0 0 8px 2px rgba(245, 166, 35, 0.7);
  }
}

@keyframes accent-glow-pulse {

  0%,
  100% {
    text-shadow: none;
  }

  50% {
    text-shadow: 0 0 40px rgba(245, 166, 35, 0.45), 0 0 80px rgba(245, 166, 35, 0.2);
  }
}

@keyframes btn-ring-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(245, 166, 35, 0.8), 0 0 20px rgba(245, 166, 35, 0.6);
  }

  65% {
    box-shadow: 0 0 0 22px rgba(245, 166, 35, 0), 0 0 40px rgba(245, 166, 35, 0);
  }

  100% {
    box-shadow: 0 0 0 0 rgba(245, 166, 35, 0), 0 0 20px rgba(245, 166, 35, 0);
  }
}

@keyframes particle-rise {
  0% {
    transform: translateY(0) scale(1);
    opacity: 0.55;
  }

  80% {
    opacity: 0.15;
  }

  100% {
    transform: translateY(-120px) scale(0.25);
    opacity: 0;
  }
}

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
}

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  will-change: transform;
}

.hero-orb-1 {
  width: 65%;
  height: 65%;
  top: 5%;
  left: -10%;
  background: radial-gradient(circle, rgba(245, 166, 35, 0.13) 0%, transparent 70%);
  animation: orb-drift-1 18s ease-in-out infinite;
}

.hero-orb-2 {
  width: 55%;
  height: 55%;
  top: -10%;
  right: -5%;
  background: radial-gradient(circle, rgba(78, 205, 196, 0.1) 0%, transparent 70%);
  animation: orb-drift-2 23s ease-in-out infinite;
}

.hero-orb-3 {
  width: 45%;
  height: 45%;
  bottom: -5%;
  left: 28%;
  background: radial-gradient(circle, rgba(232, 67, 62, 0.09) 0%, transparent 70%);
  animation: orb-drift-3 16s ease-in-out infinite;
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-sub {
  font-family: 'Outfit', sans-serif;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--accent3);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 16px;
  animation: hero-fade-up 0.8s cubic-bezier(0.22, 1, 0.36, 1) 0.2s both;
}

.hero-title {
  font-size: clamp(3rem, 8vw, 6rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
  animation: hero-fade-up 0.9s cubic-bezier(0.22, 1, 0.36, 1) 0.45s both;
}

.hero-title .accent {
  display: inline-block;
  animation: accent-glow-pulse 4s ease-in-out 1.6s infinite;
}

.hero-desc {
  font-size: 1.2rem;
  color: var(--text-dim);
  max-width: 500px;
  margin: 0 auto 40px;
  animation: hero-fade-up 0.9s cubic-bezier(0.22, 1, 0.36, 1) 0.7s both;
}

.btn-primary {
  display: inline-block;
  padding: 14px 40px;
  background: var(--accent);
  color: var(--bg);
  font-weight: 700;
  font-size: 1rem;
  border-radius: 50px;
  transition: background 0.3s, transform 0.3s, box-shadow 0.3s;
  letter-spacing: 0.02em;
  animation: hero-fade-up 0.9s cubic-bezier(0.22, 1, 0.36, 1) 0.95s both,
    btn-ring-pulse 2.6s ease-out 2.2s infinite;
}

.btn-primary:hover {
  background: var(--accent3);
  color: var(--bg);
  transform: translateY(-3px);
  box-shadow: 0 10px 36px rgba(245, 166, 35, 0.4);
  animation: none;
}

.hero-strings {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
  z-index: 1;
}

.hero-strings span {
  position: absolute;
  left: 0;
  right: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(245, 166, 35, 0.55) 30%, rgba(245, 166, 35, 0.85) 50%, rgba(245, 166, 35, 0.55) 70%, transparent 100%);
}

.hero-strings span:nth-child(1) {
  top: 20%;
  height: 1px;
  animation: string-shimmer 3.6s ease-in-out 0.3s infinite;
}

.hero-strings span:nth-child(2) {
  top: 33%;
  height: 1px;
  animation: string-shimmer 4.3s ease-in-out 1.2s infinite;
}

.hero-strings span:nth-child(3) {
  top: 46%;
  height: 1.5px;
  animation: string-shimmer 3.9s ease-in-out 0.8s infinite;
}

.hero-strings span:nth-child(4) {
  top: 59%;
  height: 1.5px;
  animation: string-shimmer 4.9s ease-in-out 1.9s infinite;
}

.hero-strings span:nth-child(5) {
  top: 72%;
  height: 2px;
  animation: string-shimmer 5.3s ease-in-out 2.5s infinite;
}

.hero-strings span:nth-child(6) {
  top: 85%;
  height: 2px;
  animation: string-shimmer 4.6s ease-in-out 0.6s infinite;
}

.hero-particles {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
}

.hero-particles span {
  position: absolute;
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: rgba(245, 166, 35, 0.65);
}

.hero-particles span:nth-child(1) {
  left: 14%;
  bottom: 28%;
  animation: particle-rise 7.2s ease-in 1.0s infinite;
}

.hero-particles span:nth-child(2) {
  left: 27%;
  bottom: 38%;
  animation: particle-rise 9.1s ease-in 2.6s infinite;
}

.hero-particles span:nth-child(3) {
  left: 43%;
  bottom: 22%;
  animation: particle-rise 8.0s ease-in 0.4s infinite;
}

.hero-particles span:nth-child(4) {
  left: 61%;
  bottom: 32%;
  animation: particle-rise 6.5s ease-in 3.3s infinite;
}

.hero-particles span:nth-child(5) {
  left: 76%;
  bottom: 24%;
  animation: particle-rise 10.2s ease-in 1.4s infinite;
}

.hero-particles span:nth-child(6) {
  left: 86%;
  bottom: 42%;
  animation: particle-rise 7.8s ease-in 4.1s infinite;
}

.hero-particles span:nth-child(7) {
  left: 51%;
  bottom: 48%;
  animation: particle-rise 8.7s ease-in 0.2s infinite;
}

/* ===== SECTIONS ===== */
.section {
  padding: 100px 0;
}

.section-dark {
  background: var(--bg-dark);
}

.section-title {
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 900;
  text-align: center;
  margin-bottom: 16px;
}

.section-desc {
  text-align: center;
  color: rgba(255, 255, 255, 0.55);
  font-size: 1.05rem;
  font-weight: 400;
  max-width: 600px;
  margin: 0 auto 60px;
}

/* ===== INTRO ===== */
.intro-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 60px;
}

.intro-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
}

.intro-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
}

.intro-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.intro-card h3 {
  font-size: 1.2rem;
  margin-bottom: 12px;
  color: var(--accent);
}

.intro-card p {
  color: var(--text-dim);
  font-size: 0.95rem;
}

/* ===== COMPARISON TABLE ===== */
.comparison-table {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow);
}

.comparison-table h3 {
  text-align: center;
  margin-bottom: 24px;
  font-size: 1.3rem;
}

.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  padding: 14px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

th {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

td:first-child {
  font-weight: 700;
  color: var(--text);
}

td {
  color: var(--text-dim);
  font-size: 0.95rem;
}

tr:last-child td {
  border-bottom: none;
}

/* ===== CHORD EVOLUTION ===== */
.chord-evolution {
  margin-bottom: 60px;
}

.chord-evolution h3,
.chord-shapes h3 {
  text-align: center;
  font-size: 1.4rem;
  margin-bottom: 36px;
}

.evolution-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.evo-step {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  min-width: 140px;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
}

.evo-step:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
}

.evo-step.highlight {
  border-color: var(--accent);
  box-shadow: 0 0 30px rgba(245, 166, 35, 0.15);
}

.evo-level {
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 0.8rem;
  color: var(--accent3);
  margin-bottom: 8px;
}

.evo-name {
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 4px;
}

.evo-notes {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.evo-arrow {
  font-size: 1.5rem;
  color: var(--accent);
  font-weight: 700;
}

/* ===== CHORD SHAPES ===== */
.shapes-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.shape-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  transition: border-color 0.3s;
}

.shape-card:hover {
  border-color: var(--accent);
}

.shape-card h4 {
  font-size: 1.1rem;
  margin-bottom: 16px;
  color: var(--accent);
}

.shape-card p {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-top: 16px;
}

/* ===== FRETBOARD (SVG diagram, 45° rotated) ===== */
.fretboard {
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px 0;
  overflow: visible;
}

.fretboard svg {
  display: block;
  margin: 0 auto;
}

.fretboard.mini svg {
  max-height: 70px;
}

/* ===== CHORD TONE SECTION ===== */
.chord-tone-section {
  margin-top: 24px;
  padding: 24px;
  background: rgba(245, 166, 35, 0.05);
  border: 1px solid rgba(245, 166, 35, 0.2);
  border-radius: var(--radius);
}

.chord-tone-section h4 {
  color: var(--accent);
  margin-bottom: 16px;
  font-size: 1.1rem;
}

.chord-tone-grid {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.chord-tone-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  text-align: center;
  min-width: 160px;
}

.chord-tone-name {
  font-family: 'Outfit', sans-serif;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
}

.chord-tone-notes {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-bottom: 8px;
}

.ct-note {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.9rem;
  line-height: 1;
  justify-content: center;
}

.ct-note small {
  font-size: 0.6rem;
  opacity: 0.7;
  font-weight: 400;
}

.ct-note.root {
  background: var(--accent);
  color: #1a1a2e;
}

.ct-note.third {
  background: var(--accent2);
  color: #fff;
}

.ct-note.fifth {
  background: var(--accent3);
  color: #1a1a2e;
}

.ct-note.seventh {
  background: var(--accent4);
  color: #fff;
}

.chord-tone-tip {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 8px;
}

.chord-tone-practice {
  margin-top: 24px;
  padding: 20px;
  background: rgba(78, 205, 196, 0.05);
  border: 1px solid rgba(78, 205, 196, 0.2);
  border-radius: var(--radius);
}

.chord-tone-practice h4 {
  color: var(--accent3);
  margin-bottom: 12px;
}

.chord-tone-practice ol {
  padding-left: 20px;
}

.chord-tone-practice li {
  margin-bottom: 8px;
  line-height: 1.6;
}

.chromatic-examples {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.chromatic-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
}

.chromatic-name {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.chromatic-notation {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

.chromatic-arrow {
  color: var(--accent);
  font-size: 1.2rem;
  font-weight: 700;
}

.chromatic-item p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.shape-group-title {
  color: var(--accent);
  font-family: 'Outfit', sans-serif;
  font-size: 1.2rem;
  margin-top: 40px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

/* ===== SCALE ROADMAP ===== */
.scale-roadmap {
  max-width: 800px;
  margin: 0 auto;
}

.roadmap-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 0;
  position: relative;
  box-shadow: var(--shadow);
}

.roadmap-item.already-know {
  border-color: var(--accent3);
  box-shadow: 0 0 30px rgba(78, 205, 196, 0.1);
}

.roadmap-item.step-3 {
  border-color: var(--accent2);
}

.roadmap-badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
  background: var(--accent3);
  color: var(--bg);
}

.roadmap-badge.step {
  background: var(--accent);
  color: var(--bg);
}

.roadmap-item h3 {
  font-size: 1.3rem;
  margin-bottom: 8px;
}

.scale-notes {
  font-family: 'Outfit', sans-serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 4px;
  letter-spacing: 0.05em;
}

.scale-degrees {
  font-family: 'Outfit', sans-serif;
  font-size: 0.9rem;
  color: var(--text-dim);
  margin-bottom: 16px;
}

/* Scale visualization bar */
.scale-bar {
  position: relative;
  height: 50px;
  background: linear-gradient(90deg, rgba(245, 166, 35, 0.05), rgba(78, 205, 196, 0.05));
  border-radius: 25px;
  margin: 16px 0;
  border: 1px solid var(--border);
}

.note-dot {
  position: absolute;
  left: calc(var(--pos) * 0.85 + 7.5%);
  top: 50%;
  transform: translate(-50%, -50%);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 700;
  font-family: 'Outfit', sans-serif;
}

.note-dot.new {
  background: var(--accent3);
  box-shadow: 0 0 15px rgba(78, 205, 196, 0.4);
}

.note-dot.accent-dot {
  background: var(--accent2);
}

.note-dot.danger {
  background: var(--accent4);
  box-shadow: 0 0 15px rgba(167, 139, 250, 0.4);
}

.scale-tip {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-top: 12px;
}

.roadmap-connector {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px 0;
}

.roadmap-connector span {
  background: var(--accent);
  color: var(--bg);
  padding: 6px 20px;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 700;
}

/* ===== PROGRESSIONS ===== */
.prog-cards {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.prog-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow);
}

.prog-card.main-prog {
  border-color: var(--accent);
  box-shadow: 0 0 40px rgba(245, 166, 35, 0.08);
}

.prog-badge {
  display: inline-block;
  background: var(--accent);
  color: var(--bg);
  padding: 4px 14px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.prog-card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.prog-desc {
  color: var(--text-dim);
  margin-bottom: 24px;
}

.prog-example {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 24px;
  margin-bottom: 20px;
}

.prog-key {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  color: var(--accent3);
  font-size: 0.85rem;
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}

.prog-chords {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.prog-chord {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 24px;
  text-align: center;
  min-width: 100px;
}

.prog-chord.resolve {
  border-color: var(--accent);
  box-shadow: 0 0 20px rgba(245, 166, 35, 0.15);
}

.chord-name {
  display: block;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 1.3rem;
  color: var(--text);
}

.chord-role {
  display: block;
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--accent);
  margin: 4px 0;
}

.chord-scale {
  display: block;
  font-size: 0.75rem;
  color: var(--text-dim);
}

.prog-arrow {
  font-size: 1.5rem;
  color: var(--accent);
}

.prog-rock-compare {
  background: rgba(78, 205, 196, 0.05);
  border: 1px solid rgba(78, 205, 196, 0.2);
  border-radius: var(--radius-sm);
  padding: 20px;
}

.prog-rock-compare h4 {
  color: var(--accent3);
  margin-bottom: 8px;
  font-size: 0.95rem;
}

.prog-rock-compare p {
  color: var(--text-dim);
  font-size: 0.9rem;
}

.prog-tip {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-top: 12px;
}

/* Blues Grid */
.prog-blues {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.blues-bar {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 12px;
  text-align: center;
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
}

/* ===== TECHNIQUES ===== */
.tech-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.tech-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--shadow);
  transition: border-color 0.3s;
}

.tech-card:hover {
  border-color: var(--accent);
}

.tech-number {
  font-family: 'Outfit', sans-serif;
  font-size: 2.5rem;
  font-weight: 800;
  color: rgba(245, 166, 35, 0.15);
  line-height: 1;
  margin-bottom: 8px;
}

.tech-card h3 {
  font-size: 1.2rem;
  margin-bottom: 16px;
  color: var(--accent);
}

.tech-detail p {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-bottom: 12px;
}

.tech-example {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 20px;
  margin: 16px 0;
}

.tech-example h4 {
  font-size: 0.9rem;
  color: var(--accent3);
  margin-bottom: 12px;
}

.tech-example ol,
.tech-example ul {
  padding-left: 20px;
  color: var(--text-dim);
  font-size: 0.9rem;
}

.tech-example li {
  margin-bottom: 6px;
}

.tech-tip {
  color: var(--accent3) !important;
  font-style: italic;
}

/* ===== METRONOME / TOOLS ===== */
.metronome-card {
  max-width: 560px;
  margin: 0 auto;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  text-align: center;
  box-shadow: var(--shadow);
}

.metronome-card h3 {
  font-size: 1.4rem;
  margin-bottom: 8px;
  color: var(--accent);
}

.metronome-desc {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-bottom: 32px;
}

.metronome-display {
  margin-bottom: 20px;
}

.metronome-bpm-display {
  font-family: 'Outfit', sans-serif;
  font-size: 4.5rem;
  font-weight: 800;
  color: var(--text);
  line-height: 1;
  letter-spacing: -0.02em;
}

.metronome-bpm-label {
  font-family: 'Outfit', sans-serif;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-dim);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.metronome-beats {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 28px;
}

.beat-indicator {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--border);
  transition: background 0.08s, box-shadow 0.08s, transform 0.08s;
}

.beat-indicator.active {
  background: var(--accent);
  box-shadow: 0 0 18px rgba(245, 166, 35, 0.6);
  transform: scale(1.2);
}

.beat-indicator.active-accent {
  background: var(--accent2);
  box-shadow: 0 0 18px rgba(232, 67, 62, 0.6);
  transform: scale(1.3);
}

.metronome-controls {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.metronome-bpm-control {
  display: flex;
  align-items: center;
  gap: 8px;
}

.bpm-btn {
  width: 44px;
  height: 38px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s;
}

.bpm-btn:hover {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}

.bpm-input {
  width: 72px;
  height: 38px;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  text-align: center;
  appearance: textfield;
  -moz-appearance: textfield;
}

.bpm-input::-webkit-inner-spin-button,
.bpm-input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.bpm-input:focus {
  outline: none;
  border-color: var(--accent);
}

.bpm-slider {
  width: 100%;
  max-width: 400px;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: var(--border);
  border-radius: 3px;
  outline: none;
}

.bpm-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  box-shadow: 0 0 10px rgba(245, 166, 35, 0.3);
  transition: transform 0.15s;
}

.bpm-slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

.bpm-slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
  box-shadow: 0 0 10px rgba(245, 166, 35, 0.3);
}

.metronome-options {
  display: flex;
  align-items: center;
  gap: 16px;
}

.metronome-time-sig {
  display: flex;
  align-items: center;
  gap: 8px;
}

.metronome-time-sig label {
  font-size: 0.9rem;
  color: var(--text-dim);
  font-weight: 600;
}

.time-sig-select {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 6px 12px;
  cursor: pointer;
}

.time-sig-select:focus {
  outline: none;
  border-color: var(--accent);
}

.metronome-play-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 200px;
  height: 52px;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: 50px;
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 1.05rem;
  cursor: pointer;
  transition: all 0.2s;
}

.metronome-play-btn:hover {
  background: var(--accent3);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 166, 35, 0.3);
}

.metronome-play-btn.playing {
  background: var(--accent2);
}

.metronome-play-btn.playing:hover {
  background: #c9342f;
  box-shadow: 0 6px 20px rgba(232, 67, 62, 0.3);
}

.play-icon {
  font-size: 1.1rem;
  line-height: 1;
}

.metronome-presets {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 24px;
  flex-wrap: wrap;
}

.preset-label {
  font-size: 0.8rem;
  color: var(--text-dim);
  font-weight: 600;
}

.preset-btn {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: 50px;
  color: var(--text-dim);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.8rem;
  padding: 4px 14px;
  cursor: pointer;
  transition: all 0.2s;
}

.preset-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ===== CHORD PLAYER ===== */
.chord-player-card {
  max-width: 720px;
  margin: 48px auto 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  text-align: center;
  box-shadow: var(--shadow);
}

.chord-player-card h3 {
  font-size: 1.4rem;
  margin-bottom: 8px;
  color: var(--accent);
}

.chord-player-desc {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-bottom: 28px;
}

.song-selector {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-bottom: 24px;
}

.song-tab {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: 50px;
  color: var(--text-dim);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.8rem;
  padding: 6px 16px;
  cursor: pointer;
  transition: all 0.2s;
}

.song-tab:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.song-tab.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
}

.chart-info {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 16px;
}

.chart-key,
.chart-form {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--accent3);
  letter-spacing: 0.03em;
}

.chord-chart {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
  margin-bottom: 28px;
}

.chart-bar {
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px 6px;
  text-align: center;
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.82rem;
  color: var(--text-dim);
  transition: all 0.12s;
  min-height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.chart-bar .bar-chords {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
}

.chart-bar .bar-divider {
  color: rgba(255, 255, 255, 0.15);
  font-weight: 400;
}

.chart-bar.active {
  background: rgba(245, 166, 35, 0.15);
  border-color: var(--accent);
  color: var(--text);
  box-shadow: 0 0 12px rgba(245, 166, 35, 0.2);
}

.chord-player-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.chord-play-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-width: 140px;
  height: 46px;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: 50px;
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.2s;
}

.chord-play-btn:hover {
  background: var(--accent3);
  transform: translateY(-2px);
}

.chord-play-btn.playing {
  background: var(--accent2);
}

.chord-play-btn.playing:hover {
  background: #c9342f;
}

.chord-bpm-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chord-bpm-val {
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 1.2rem;
  color: var(--text);
  min-width: 36px;
  text-align: center;
}

.chord-bpm-unit {
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.75rem;
  color: var(--text-dim);
  margin-right: 4px;
}

.chord-bpm-slider {
  width: 100px;
}

.loop-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-dim);
  cursor: pointer;
}

.loop-label input[type="checkbox"] {
  accent-color: var(--accent);
  width: 16px;
  height: 16px;
  cursor: pointer;
}

@media (max-width: 600px) {
  .chord-player-card {
    padding: 28px 16px;
  }

  .chord-chart {
    grid-template-columns: repeat(2, 1fr);
  }

  .chord-player-controls {
    flex-direction: column;
    gap: 14px;
  }

  .chord-bpm-group {
    flex-wrap: wrap;
    justify-content: center;
  }
}

/* ===== PRACTICE ===== */
.practice-timeline {
  max-width: 800px;
  margin: 0 auto 60px;
  position: relative;
}

.practice-timeline::before {
  content: '';
  position: absolute;
  left: 60px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--accent) 0%, rgba(245, 166, 35, 0.3) 50%, rgba(255, 255, 255, 0.08) 100%);
}

.timeline-item {
  display: flex;
  gap: 32px;
  margin-bottom: 40px;
  position: relative;
}

.timeline-month {
  flex-shrink: 0;
  width: 120px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent);
  color: var(--bg);
  border-radius: 50px;
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.85rem;
  position: relative;
  z-index: 2;
}

.timeline-content {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  flex: 1;
  box-shadow: var(--shadow);
}

.timeline-content h3 {
  font-size: 1.2rem;
  margin-bottom: 16px;
  color: var(--accent);
}

.timeline-content ul {
  padding-left: 0;
  margin-bottom: 20px;
  list-style: none;
}

.timeline-content li {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-bottom: 8px;
  padding-left: 20px;
  position: relative;
}

.timeline-content li::before {
  content: '';
  position: absolute;
  left: 2px;
  top: 0.55em;
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 2px;
  transform: rotate(45deg);
}

.daily-routine {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 20px;
}

.daily-routine h4 {
  font-size: 0.9rem;
  color: var(--accent3);
  margin-bottom: 12px;
}

.routine-items {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.routine-items span {
  background: rgba(245, 166, 35, 0.1);
  border: 1px solid rgba(245, 166, 35, 0.2);
  border-radius: 50px;
  padding: 6px 16px;
  font-size: 0.85rem;
  color: var(--accent);
}

/* ===== RECOMMENDED SONGS ===== */
.recommended {
  max-width: 900px;
  margin: 0 auto;
}

.recommended h3 {
  text-align: center;
  font-size: 1.3rem;
  margin-bottom: 32px;
}

.songs-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.song-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
}

.song-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
}

.song-card .difficulty {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 50px;
  font-size: 0.7rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.song-card.easy .difficulty {
  background: rgba(78, 205, 196, 0.15);
  color: var(--accent3);
}

.song-card.medium .difficulty {
  background: rgba(245, 166, 35, 0.15);
  color: var(--accent);
}

.song-card.hard .difficulty {
  background: rgba(232, 67, 62, 0.15);
  color: var(--accent2);
}

.song-card.expert .difficulty {
  background: rgba(167, 139, 250, 0.15);
  color: var(--accent4);
}

.song-card h4 {
  font-size: 1.05rem;
  margin-bottom: 8px;
}

.song-card p {
  color: var(--text-dim);
  font-size: 0.85rem;
}

/* ===== FOOTER ===== */
.footer {
  padding: 60px 0;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer-content {
  max-width: 500px;
  margin: 0 auto;
}

.footer-logo {
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.footer-logo .logo-icon {
  color: var(--accent);
  margin-right: 8px;
}

.footer p {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.footer-quote {
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.footer-quote blockquote {
  font-style: italic;
  color: var(--text-dim);
  font-size: 1rem;
  margin-bottom: 8px;
}

.footer-quote cite {
  color: var(--accent);
  font-size: 0.85rem;
}

.footer-disclaimer {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.footer-disclaimer p {
  font-size: 0.75rem;
  color: var(--text-dim);
  line-height: 1.6;
  opacity: 0.7;
}

.footer-copyright {
  margin-top: 12px;
}

.footer-copyright p {
  font-size: 0.75rem;
  color: var(--text-dim);
  opacity: 0.6;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {

  .intro-grid,
  .shapes-grid,
  .songs-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .tech-grid {
    grid-template-columns: 1fr;
  }

  .evolution-steps {
    flex-direction: column;
  }

  .evo-arrow {
    transform: rotate(90deg);
  }

  .practice-timeline::before {
    display: none;
  }

  .timeline-item {
    flex-direction: column;
    gap: 16px;
  }

  .timeline-month {
    align-self: flex-start;
  }
}

@media (max-width: 600px) {
  .nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(10, 10, 15, 0.95);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 20px 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
  }

  .nav.open {
    display: flex;
  }

  .nav-toggle {
    display: flex;
  }

  .sub-nav-inner {
    padding: 0 12px;
    gap: 2px;
  }

  .sub-nav-link {
    padding: 5px 12px;
    font-size: 0.78rem;
  }

  .intro-grid,
  .shapes-grid,
  .songs-grid,
  .prog-blues {
    grid-template-columns: 1fr;
  }

  .prog-chords {
    flex-direction: column;
  }

  .prog-arrow {
    transform: rotate(90deg);
  }

  .section {
    padding: 60px 0;
  }

  .comparison-table {
    padding: 20px;
  }

  th,
  td {
    padding: 10px 12px;
    font-size: 0.85rem;
  }
}

/* ===== SONG CARD BUTTON ===== */
.song-chart-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 12px;
  padding: 6px 16px;
  background: rgba(245, 166, 35, 0.12);
  border: 1px solid rgba(245, 166, 35, 0.3);
  border-radius: 50px;
  color: var(--accent);
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.2s;
}

.song-chart-btn:hover {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}

/* ===== SONG MODAL ===== */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}

.modal-overlay.open {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  position: relative;
  width: 90%;
  max-width: 720px;
  max-height: 85vh;
  overflow-y: auto;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  text-align: center;
  transform: translateY(20px) scale(0.97);
  transition: transform 0.3s;
}

.modal-overlay.open .modal-content {
  transform: translateY(0) scale(1);
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 16px;
  background: none;
  border: none;
  color: var(--text-dim);
  font-size: 2rem;
  line-height: 1;
  cursor: pointer;
  transition: color 0.2s;
  padding: 4px 8px;
}

.modal-close:hover {
  color: var(--accent);
}

.modal-title {
  font-size: 1.4rem;
  margin-bottom: 12px;
  color: var(--accent);
}

@media (max-width: 600px) {
  .modal-content {
    width: 95%;
    padding: 28px 16px;
    max-height: 90vh;
  }

  .modal-content .chord-chart {
    grid-template-columns: repeat(2, 1fr);
  }

  .modal-content .chord-player-controls {
    flex-direction: column;
    gap: 14px;
  }

  .modal-content .chord-bpm-group {
    flex-wrap: wrap;
    justify-content: center;
  }
}

/* ===== Modal Song Description & Performances ===== */
.modal-song-desc {
  text-align: left;
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 16px;
  padding: 0 4px;
}

.modal-performances {
  text-align: left;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.modal-perf-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
}

.modal-perf-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  margin-bottom: 10px;
}

.modal-perf-item:last-child {
  margin-bottom: 0;
}

.modal-perf-artist {
  font-weight: 700;
  color: var(--accent);
  font-size: 0.9rem;
}

.modal-perf-album {
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 4px;
  font-style: italic;
}

.modal-perf-desc {
  font-size: 0.85rem;
  color: var(--text);
  line-height: 1.5;
}

/* ===== ANIMATIONS ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== SUB-NAVIGATION ===== */
.sub-nav {
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  z-index: 999;
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  height: 48px;
}

.sub-nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  height: 100%;
  gap: 4px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.sub-nav-inner::-webkit-scrollbar {
  display: none;
}

.sub-nav-link {
  flex-shrink: 0;
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-dim);
  transition: all 0.2s;
  white-space: nowrap;
}

.sub-nav-link:hover {
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}

.sub-nav-link.active {
  color: var(--bg);
  background: var(--accent);
}

/* ===== PAGE TOP SECTION (offset for fixed header + subnav) ===== */
.page-top-section {
  padding-top: 180px;
}

/* ===== PAGE NAV CARDS (index.html) ===== */
.page-nav-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 60px;
}

.page-nav-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
  color: var(--text);
}

.page-nav-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  color: var(--text);
}

.page-nav-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.page-nav-card h3 {
  font-size: 1.1rem;
  margin-bottom: 8px;
  color: var(--accent);
}

.page-nav-card p {
  color: var(--text-dim);
  font-size: 0.85rem;
}

@media (max-width: 600px) {
  .page-nav-cards {
    grid-template-columns: 1fr 1fr;
  }
}

/* ===== FOOTER NAV ===== */
.footer-nav {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.footer-nav a {
  color: var(--text-dim);
  font-size: 0.85rem;
  font-weight: 600;
  transition: color 0.2s;
}

.footer-nav a:hover {
  color: var(--accent);
}

/* ===== NAV ACTIVE LINK ===== */
.nav a.active {
  color: var(--accent);
}

.nav a.active::after {
  width: 100%;
}

/* ===== FRETBOARD PLAY BUTTON ===== */
.fretboard-play-btn {
  position: absolute;
  bottom: 2px;
  right: 2px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: rgba(245, 166, 35, 0.1);
  color: var(--accent);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
  padding: 0;
  z-index: 5;
}

.fretboard-play-btn:hover {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
  transform: scale(1.1);
}

.fretboard-play-btn.playing {
  background: var(--accent3);
  border-color: var(--accent3);
  color: var(--bg);
  animation: pulse-play 0.4s ease;
}

@keyframes pulse-play {
  0% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.2);
  }

  100% {
    transform: scale(1);
  }
}

.fretboard.mini .fretboard-play-btn {
  width: 22px;
  height: 22px;
  bottom: 0;
  right: -4px;
}

.fretboard.mini .fretboard-play-btn svg {
  width: 12px;
  height: 12px;
}

/* ===== GLOSSARY ===== */
.glossary-controls {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  margin-bottom: 40px;
}

.glossary-search {
  width: 100%;
  max-width: 400px;
}

.glossary-search-input {
  width: 100%;
  padding: 12px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 50px;
  color: var(--text);
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-size: 0.95rem;
  outline: none;
  transition: border-color 0.2s;
}

.glossary-search-input:focus {
  border-color: var(--accent);
}

.glossary-search-input::placeholder {
  color: var(--text-dim);
}

.glossary-filters {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}

.glossary-filter-btn {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: 50px;
  color: var(--text-dim);
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.8rem;
  padding: 6px 18px;
  cursor: pointer;
  transition: all 0.2s;
}

.glossary-filter-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.glossary-filter-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
}

.glossary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.glossary-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: border-color 0.3s, transform 0.3s;
}

.glossary-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.glossary-card-header {
  margin-bottom: 12px;
}

.glossary-badge {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 50px;
  font-size: 0.7rem;
  font-weight: 700;
}

.glossary-badge-theory {
  background: rgba(245, 166, 35, 0.15);
  color: var(--accent);
}

.glossary-badge-technique {
  background: rgba(78, 205, 196, 0.15);
  color: var(--accent3);
}

.glossary-badge-style {
  background: rgba(167, 139, 250, 0.15);
  color: var(--accent4);
}

.glossary-badge-session {
  background: rgba(232, 67, 62, 0.15);
  color: var(--accent2);
}

.glossary-term-en {
  font-family: 'Outfit', sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 2px;
}

.glossary-term-ja {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 10px;
}

.glossary-desc {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.6;
  margin-bottom: 8px;
}

.glossary-context {
  font-size: 0.8rem;
  color: var(--text-dim);
  font-style: italic;
  opacity: 0.7;
}

.glossary-no-results {
  text-align: center;
  color: var(--text-dim);
  font-size: 1rem;
  padding: 40px 0;
}

@media (max-width: 900px) {
  .glossary-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .glossary-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== SESSION ETIQUETTE ===== */
.etiquette-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

.etiquette-card h3 {
  font-size: 1.3rem;
  margin-bottom: 20px;
  color: var(--accent);
}

.etiquette-list {
  list-style: none;
  padding: 0;
}

.etiquette-list li {
  padding: 10px 0 10px 24px;
  position: relative;
  color: var(--text-dim);
  font-size: 0.92rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.etiquette-list li:last-child {
  border-bottom: none;
}

.etiquette-list li::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 1.1em;
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 2px;
  transform: rotate(45deg);
}

.signal-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.signal-item {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
}

.signal-gesture {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--accent3);
  margin-bottom: 8px;
}

.signal-meaning {
  font-size: 0.85rem;
  color: var(--text-dim);
}

.dos-donts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.dos h4,
.donts h4 {
  font-size: 1rem;
  margin-bottom: 12px;
}

.dos ul,
.donts ul {
  list-style: none;
  padding: 0;
}

.dos li,
.donts li {
  padding: 8px 0 8px 20px;
  position: relative;
  color: var(--text-dim);
  font-size: 0.88rem;
}

.dos li::before {
  content: '\2713';
  position: absolute;
  left: 0;
  color: var(--accent3);
  font-weight: 700;
}

.donts li::before {
  content: '\2717';
  position: absolute;
  left: 0;
  color: var(--accent2);
  font-weight: 700;
}

@media (max-width: 600px) {
  .signal-grid {
    grid-template-columns: 1fr 1fr;
  }

  .dos-donts {
    grid-template-columns: 1fr;
  }
}

/* ===== NEWS ===== */
.news-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 32px;
}

.news-refresh-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border);
  border-radius: 50px;
  color: var(--text-dim);
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s;
}

.news-refresh-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.news-refresh-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.news-refresh-icon {
  font-size: 1.1rem;
}

.news-cache-info {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.news-loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 60px 0;
  color: var(--text-dim);
}

.news-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.news-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
  display: flex;
  flex-direction: column;
  color: var(--text);
  text-decoration: none;
}

.news-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  color: var(--text);
}

.news-card-thumb {
  width: 100%;
  height: 160px;
  overflow: hidden;
  background: rgba(0, 0, 0, 0.3);
}

.news-card-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}

.news-card:hover .news-card-thumb img {
  transform: scale(1.05);
}

.news-card-body {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.news-card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.news-source {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.03em;
}

.news-date {
  font-size: 0.75rem;
  color: var(--text-dim);
}

.news-card-title {
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 8px;
  color: var(--text);
}

.news-card-desc {
  font-size: 0.82rem;
  color: var(--text-dim);
  line-height: 1.5;
  flex: 1;
}

.news-error {
  text-align: center;
  padding: 60px 0;
}

.news-error-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.news-error h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
}

.news-error p {
  color: var(--text-dim);
  margin-bottom: 24px;
}

.news-retry-btn {
  display: inline-block;
  padding: 10px 30px;
  font-size: 0.9rem;
}

@media (max-width: 900px) {
  .news-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .news-grid {
    grid-template-columns: 1fr;
  }

  .news-card-thumb {
    height: 140px;
  }
}

/* ===== Evo Fretboard Trio (Lv.5 Tensions) ===== */
.evo-fretboard-trio {
  display: flex;
  gap: 4px;
  justify-content: center;
}

/* ===== Diatonic Table ===== */
.diatonic-table-wrap {
  overflow-x: auto;
  margin-top: 32px;
}

.diatonic-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
  text-align: center;
}

.diatonic-table th,
.diatonic-table td {
  padding: 10px 8px;
  border: 1px solid var(--border);
}

.diatonic-table th {
  background: rgba(245, 166, 35, 0.1);
  color: var(--accent);
  font-weight: 700;
}

.diatonic-table .dt-maj {
  color: var(--accent);
  font-weight: 700;
}

.diatonic-table .dt-min {
  color: var(--accent3);
  font-weight: 700;
}

.diatonic-table .dt-dom {
  color: var(--accent2);
  font-weight: 700;
}

.diatonic-table .dt-dim {
  color: var(--accent4);
  font-weight: 700;
}

/* ===== Fretboard Note Map ===== */
.fretboard-map-wrap {
  overflow-x: auto;
  margin-top: 32px;
}

.fretboard-map-table {
  width: 100%;
  border-collapse: collapse;
  font-family: 'Outfit', sans-serif;
  font-size: 0.8rem;
  text-align: center;
  white-space: nowrap;
}

.fretboard-map-table th,
.fretboard-map-table td {
  padding: 8px 6px;
  border: 1px solid var(--border);
  min-width: 36px;
  text-align: center;
  vertical-align: middle;
}

.fretboard-map-table th {
  background: rgba(245, 166, 35, 0.08);
  color: var(--text-dim);
  font-weight: 600;
  font-size: 0.75rem;
}

.fretboard-map-table .string-label {
  font-weight: 700;
  color: var(--text);
  text-align: right;
  padding-right: 12px;
  background: rgba(245, 166, 35, 0.05);
}

.fretboard-map-table .fn-root {
  background: rgba(232, 67, 62, 0.2);
  color: var(--accent2);
  font-weight: 700;
}

.fretboard-map-table .fn-c {
  background: rgba(245, 166, 35, 0.1);
  color: var(--accent);
  font-weight: 600;
}

.fretboard-map-legend {
  margin-top: 12px;
  font-size: 0.8rem;
  color: var(--text-dim);
  text-align: center;
}

.fn-root-label {
  display: inline-block;
  background: rgba(232, 67, 62, 0.2);
  color: var(--accent2);
  font-weight: 700;
  padding: 1px 8px;
  border-radius: 4px;
}

.fn-c-label {
  display: inline-block;
  background: rgba(245, 166, 35, 0.1);
  color: var(--accent);
  font-weight: 600;
  padding: 1px 8px;
  border-radius: 4px;
}

/* ===== Album Cards ===== */
.album-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.album-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.album-cover-wrapper {
  margin: -24px -24px 20px -24px;
  width: calc(100% + 48px);
  flex-shrink: 0;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
  background: #111;
}

.album-cover {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.album-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

.album-card:hover .album-cover {
  transform: scale(1.05);
}

.album-tag {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 50px;
  font-size: 0.7rem;
  font-weight: 700;
  background: rgba(245, 166, 35, 0.15);
  color: var(--accent);
  margin-bottom: 10px;
}

.album-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.album-artist {
  font-size: 0.85rem;
  color: var(--text-dim);
  margin-bottom: 8px;
}

.album-year {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.album-desc {
  font-size: 0.82rem;
  color: var(--text-dim);
  line-height: 1.5;
}

/* Amazon Affiliate Button */
.album-amazon-link {
  margin-top: auto;
  padding-top: 14px;
}

.album-amazon-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.75rem;
  font-weight: 700;
  font-family: 'Outfit', sans-serif;
  color: var(--accent);
  text-decoration: none;
  border: 1px solid rgba(245, 166, 35, 0.4);
  border-radius: 50px;
  padding: 5px 13px;
  transition: background 0.2s, color 0.2s;
  letter-spacing: 0.03em;
}

.album-amazon-btn:hover {
  background: var(--accent);
  color: #111;
}

.album-amazon-btn svg {
  flex-shrink: 0;
}

/* ===== Guitarist Cards ===== */
.guitarist-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.guitarist-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: transform 0.3s, border-color 0.3s;
  display: flex;
  flex-direction: column;
}

.guitarist-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
}

.guitarist-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.guitarist-name {
  font-size: 1.05rem;
  font-weight: 700;
}

.guitarist-era {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 50px;
  font-size: 0.65rem;
  font-weight: 700;
  background: rgba(167, 139, 250, 0.15);
  color: var(--accent4);
  white-space: nowrap;
}

.guitarist-tag {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 50px;
  font-size: 0.7rem;
  font-weight: 700;
  background: rgba(78, 205, 196, 0.15);
  color: var(--accent3);
  margin-bottom: 10px;
  align-self: flex-start;
}

.guitarist-style {
  font-size: 0.82rem;
  color: var(--text-dim);
  line-height: 1.5;
  flex: 1;
}

.guitarist-yt-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 12px;
  padding: 6px 16px;
  background: rgba(232, 67, 62, 0.12);
  border: 1px solid rgba(232, 67, 62, 0.3);
  border-radius: 50px;
  color: var(--accent2);
  font-family: 'Noto Sans JP', 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  align-self: flex-start;
}

.guitarist-yt-btn:hover {
  background: var(--accent2);
  color: var(--bg);
  border-color: var(--accent2);
}

@media (max-width: 900px) {

  .album-grid,
  .guitarist-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {

  .album-grid,
  .guitarist-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== Circle of 5ths / 4ths ===== */
.circle-content {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 40px;
  align-items: start;
  margin-top: 40px;
}

.circle-diagram-card {
  background: var(--card);
  border-radius: 16px;
  padding: 24px;
  border: 1px solid var(--border);
  display: flex;
  justify-content: center;
  position: sticky;
  top: 100px;
}

.circle-visual svg {
  display: block;
  max-width: 100%;
  height: auto;
}

.circle-explanation .roadmap-item {
  margin-bottom: 0;
}

@media (max-width: 900px) {
  .circle-content {
    grid-template-columns: 1fr;
  }

  .circle-diagram-card {
    position: static;
    max-width: 400px;
    margin: 0 auto;
  }
}

/* ===== Triads ===== */
.triad-intro {
  margin-bottom: 24px;
}

.shape-group-title {
  font-size: 1.1rem;
  color: var(--accent);
  margin: 32px 0 16px;
  font-family: 'Outfit', sans-serif;
}

/* ===== Training Sections ===== */
.training-card {
  background: var(--card);
  border-radius: 16px;
  padding: 32px;
  border: 1px solid var(--border);
  margin-bottom: 32px;
}

.training-card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.training-steps {
  counter-reset: training-step;
  list-style: none;
  padding: 0;
  margin: 20px 0;
}

.training-steps li {
  counter-increment: training-step;
  position: relative;
  padding-left: 40px;
  margin-bottom: 16px;
  line-height: 1.6;
}

.training-steps li::before {
  content: counter(training-step);
  position: absolute;
  left: 0;
  top: 2px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
  font-family: 'Outfit', sans-serif;
}

.training-chord-sequence {
  background: rgba(0, 0, 0, 0.2);
  border-radius: 12px;
  padding: 20px;
  margin: 16px 0;
  font-family: 'Outfit', sans-serif;
  font-size: 0.95rem;
  line-height: 2;
  letter-spacing: 0.02em;
  color: var(--text);
  overflow-x: auto;
}

.training-chord-sequence .chord-highlight {
  color: var(--accent);
  font-weight: 700;
}

.training-tip {
  background: rgba(245, 166, 35, 0.08);
  border-left: 3px solid var(--accent);
  border-radius: 0 8px 8px 0;
  padding: 12px 16px;
  margin-top: 16px;
  font-size: 0.9rem;
  color: var(--text-dim);
}

/* ===== Standards List ===== */
.standards-section {
  margin-top: 40px;
}

.standards-table-wrap {
  overflow-x: auto;
  margin-top: 24px;
}

.standards-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.standards-table th {
  text-align: left;
  padding: 12px 16px;
  background: rgba(245, 166, 35, 0.1);
  color: var(--accent);
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 2px solid var(--border);
  white-space: nowrap;
}

.standards-table td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.standards-table tr:hover td {
  background: rgba(245, 166, 35, 0.04);
}

.standards-table .star {
  color: var(--accent);
  font-size: 1.1rem;
}

.standards-table .difficulty-badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 700;
  font-family: 'Outfit', sans-serif;
}

.standards-table .diff-beginner {
  background: rgba(78, 205, 196, 0.15);
  color: var(--accent2);
}

.standards-table .diff-intermediate {
  background: rgba(245, 166, 35, 0.15);
  color: var(--accent);
}

.standards-table .diff-advanced {
  background: rgba(229, 80, 100, 0.15);
  color: var(--accent3);
}

.standards-filter-btns {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 16px;
}

.standards-filter-btn {
  padding: 6px 16px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-dim);
  font-size: 0.82rem;
  cursor: pointer;
  transition: all 0.2s;
  font-family: 'Outfit', sans-serif;
}

.standards-filter-btn.active,
.standards-filter-btn:hover {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}

@media (max-width: 600px) {
  .standards-table {
    font-size: 0.8rem;
  }

  .standards-table th,
  .standards-table td {
    padding: 8px 10px;
  }

  .training-card {
    padding: 20px;
  }
}

/* ===== FRETBOARD TOOL CARD ===== */
.fretboard-tool-card {
  max-width: 560px;
  margin: 32px auto 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  text-align: center;
  box-shadow: var(--shadow);
}

.fretboard-tool-card h3 {
  font-size: 1.4rem;
  margin-bottom: 8px;
  color: var(--accent);
}

.fretboard-tool-desc {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-bottom: 24px;
}

.fretboard-open-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: 999px;
  padding: 12px 32px;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s;
}

.fretboard-open-btn:hover {
  background: #d48c1a;
  transform: translateY(-2px);
}

/* ===== FRETBOARD MODAL ===== */
.fretboard-modal-content {
  position: relative;
  width: 96vw;
  max-width: 1440px;
  height: 80vh;
  max-height: 640px;
  background: #111118;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transform: translateY(20px) scale(0.97);
  transition: transform 0.3s;
}

.modal-overlay.open .fretboard-modal-content {
  transform: translateY(0) scale(1);
}

.fretboard-modal-close {
  position: absolute;
  top: 10px;
  right: 14px;
  z-index: 10;
  background: rgba(0, 0, 0, 0.6);
  border-radius: 50%;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  line-height: 1;
  padding: 0;
}

.fretboard-iframe {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}


/* ===== FRETBOARD INLINE EMBED (playing/fretboard.html) ===== */
.fretboard-inline-embed {
  margin-top: 40px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-card);
  box-shadow: var(--shadow);
}

.fretboard-inline-header {
  padding: 24px 28px 20px;
  border-bottom: 1px solid var(--border);
}

.fretboard-inline-header h3 {
  font-size: 1.2rem;
  color: var(--accent);
  margin-bottom: 6px;
}

.fretboard-inline-header p {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.6;
}

.fretboard-inline-frame-wrap {
  position: relative;
  width: 100%;
  height: 75vh;
  min-height: 550px;
  max-height: 620px;
}

.fretboard-inline-frame {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
  background: #111118;
}

/* ===== GEAR PAGE ===== */
.gear-category {
  margin-bottom: 64px;
}

.gear-category-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  gap: 10px;
}

.gear-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.gear-card {
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
}

.gear-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.35);
}

.gear-img-link {
  display: block;
  background: #fff;
  padding: 24px;
  text-align: center;
  flex-shrink: 0;
  min-height: 120px;
}

.gear-img-link.gear-img-missing {
  background: rgba(255, 255, 255, 0.04);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 120px;
}

.gear-img-link.gear-img-missing::after {
  content: '📷';
  font-size: 2rem;
  opacity: 0.3;
}

.gear-img {
  width: 160px;
  height: 160px;
  object-fit: contain;
  display: block;
  margin: 0 auto;
}

.gear-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.gear-badge {
  display: inline-block;
  padding: 2px 10px;
  background: rgba(245, 166, 35, 0.12);
  border: 1px solid rgba(245, 166, 35, 0.3);
  border-radius: 100px;
  font-size: 0.72rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 10px;
  white-space: nowrap;
}

.gear-name {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 10px;
  line-height: 1.45;
}

.gear-catch {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 18px;
  flex: 1;
}

.gear-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 9px 20px;
  background: #FF9900;
  color: #111;
  border-radius: 100px;
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
  align-self: flex-start;
}

.gear-btn:hover {
  background: #e68900;
  transform: scale(1.03);
}

.gear-disclaimer {
  margin-top: 48px;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: var(--radius);
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ===== AFFILIATE BOOK CARDS ===== */
.book-rec-section {
  margin-top: 48px;
  padding: 28px 32px;
  background: rgba(245, 166, 35, 0.04);
  border: 1px solid rgba(245, 166, 35, 0.18);
  border-radius: var(--radius);
}

.book-rec-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}

.book-rec-header-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--accent);
}

.book-rec-disclosure {
  font-size: 0.72rem;
  color: var(--text-dim);
  margin-left: auto;
  opacity: 0.7;
}

.book-rec-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.book-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color 0.25s, transform 0.2s;
}

.book-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.book-card-emoji {
  font-size: 1.8rem;
  line-height: 1;
}

.book-card-title {
  font-family: 'Outfit', sans-serif;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.4;
}

.book-card-author {
  font-size: 0.75rem;
  color: var(--text-dim);
}

.book-card-desc {
  font-size: 0.8rem;
  color: var(--text-dim);
  line-height: 1.55;
  flex: 1;
}

.book-card-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 14px;
  background: var(--accent);
  color: #1a1a2e;
  border-radius: var(--radius-sm);
  font-size: 0.78rem;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
  margin-top: auto;
}

.book-card-link:hover {
  background: #e8940f;
  color: #1a1a2e;
  transform: translateY(-1px);
}

@media (max-width: 900px) {
  .book-rec-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .book-rec-grid {
    grid-template-columns: 1fr;
  }

  .book-rec-section {
    padding: 20px;
  }
}

/* ===== SUPPORT BUTTON ===== */
.footer-support {
  margin-top: 28px;
  text-align: center;
}

.support-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  background: linear-gradient(135deg, #346AA9, #00AAE4);
  color: #fff;
  border-radius: 50px;
  border: none;
  font-family: 'Outfit', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 20px rgba(0, 170, 228, 0.35);
  letter-spacing: 0.02em;
}

.support-btn:hover {
  opacity: 0.9;
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(0, 170, 228, 0.5);
}

.support-btn-icon {
  font-size: 1.1rem;
}

.footer-support-note {
  margin-top: 10px;
  font-size: 0.75rem;
  color: var(--text-dim);
}

/* ===== XRP MODAL ===== */
.xrp-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 2000;
  align-items: center;
  justify-content: center;
}

.xrp-modal.open {
  display: flex;
}

.xrp-modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(4px);
}

.xrp-modal-box {
  position: relative;
  background: var(--bg-card);
  border: 1px solid rgba(0, 170, 228, 0.4);
  border-radius: 20px;
  padding: 36px 32px 28px;
  width: min(440px, 90vw);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.6), 0 0 40px rgba(0, 170, 228, 0.1);
  text-align: center;
  animation: xrp-modal-in 0.2s ease;
}

@keyframes xrp-modal-in {
  from {
    opacity: 0;
    transform: scale(0.94) translateY(8px);
  }

  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

.xrp-modal-close {
  position: absolute;
  top: 14px;
  right: 18px;
  background: none;
  border: none;
  color: var(--text-dim);
  font-size: 1.5rem;
  cursor: pointer;
  line-height: 1;
  transition: color 0.2s;
  padding: 4px 8px;
}

.xrp-modal-close:hover {
  color: var(--text);
}

.xrp-modal-logo {
  font-size: 2rem;
  margin-bottom: 4px;
}

.xrp-modal-title {
  font-family: 'Outfit', sans-serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: #00AAE4;
  margin-bottom: 8px;
}

.xrp-modal-desc {
  font-size: 0.85rem;
  color: var(--text-dim);
  margin-bottom: 20px;
  line-height: 1.6;
}

.xrp-qr-wrap {
  display: flex;
  justify-content: center;
  margin-bottom: 20px;
}

.xrp-qr-img {
  border-radius: 12px;
  border: 4px solid #fff;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  display: block;
}

.xrp-address-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  margin-bottom: 14px;
}

.xrp-address {
  font-family: 'Courier New', monospace;
  font-size: 0.75rem;
  color: #00AAE4;
  word-break: break-all;
  text-align: left;
  flex: 1;
  line-height: 1.5;
}

.xrp-copy-btn {
  flex-shrink: 0;
  background: rgba(0, 170, 228, 0.15);
  border: 1px solid rgba(0, 170, 228, 0.3);
  border-radius: var(--radius-sm);
  color: #00AAE4;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 6px 12px;
  cursor: pointer;
  transition: background 0.2s;
  white-space: nowrap;
}

.xrp-copy-btn:hover {
  background: rgba(0, 170, 228, 0.3);
}

.xrp-notice {
  font-size: 0.72rem;
  color: var(--text-dim);
  line-height: 1.5;
  opacity: 0.7;
}

/* ===== UPPER STRUCTURE TRIADS ===== */
.ust-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-top: 24px;
}

.ust-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: border-color 0.3s;
}

.ust-card:hover {
  border-color: var(--accent4);
}

.ust-layer-label {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  margin-bottom: 5px;
}

.ust-triad-name {
  font-family: 'Outfit', sans-serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 10px;
}

.ust-base {
  border-top: 1px dashed rgba(255, 255, 255, 0.12);
  padding-top: 12px;
  margin-top: 12px;
}

.ust-base .ust-triad-name {
  color: var(--text-dim);
  font-size: 0.95rem;
}

.ust-result {
  margin-top: 14px;
  padding: 8px 12px;
  background: rgba(167, 139, 250, 0.08);
  border: 1px solid rgba(167, 139, 250, 0.2);
  border-radius: var(--radius-sm);
  font-family: 'Outfit', sans-serif;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent4);
}

.ust-sound {
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-top: 8px;
  line-height: 1.5;
}

/* ===== TONALITY SECTION ===== */
.tonal-compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 20px;
}

.tonal-compare-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.tonal-compare-card.major {
  border-color: rgba(78, 205, 196, 0.4);
  box-shadow: 0 0 20px rgba(78, 205, 196, 0.06);
}

.tonal-compare-card.minor {
  border-color: rgba(167, 139, 250, 0.4);
  box-shadow: 0 0 20px rgba(167, 139, 250, 0.06);
}

.tonal-compare-title {
  font-family: 'Outfit', sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 14px;
}

.tonal-compare-card.major .tonal-compare-title {
  color: var(--accent3);
}

.tonal-compare-card.minor .tonal-compare-title {
  color: var(--accent4);
}

.tonal-compare-card ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.tonal-compare-card li {
  padding: 7px 0;
  font-size: 0.88rem;
  color: var(--text-dim);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}

.tonal-compare-card li:last-child {
  border-bottom: none;
}

.tonal-compare-card li .li-label {
  color: var(--text-dim);
  font-size: 0.8rem;
}

.tonal-compare-card li .li-val {
  color: var(--text);
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
}

@media (max-width: 600px) {
  .ust-grid {
    grid-template-columns: 1fr;
  }

  .tonal-compare-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 900px) {
  .gear-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .gear-grid {
    grid-template-columns: 1fr;
  }

  .gear-img {
    width: 130px;
    height: 130px;
  }
}

/* ===== SOCIAL SHARE ===== */
.social-share-container {
  margin-top: 60px;
  text-align: center;
}

.social-share-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

.social-share-title .ja {
  margin-right: 12px;
}

.social-share-buttons {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.social-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  color: #fff;
  text-decoration: none;
  transition: transform 0.2s, opacity 0.2s;
  border: none;
  cursor: pointer;
}

.social-btn:hover {
  transform: translateY(-2px);
  opacity: 0.9;
  color: #fff;
}

.social-btn.x-btn {
  background: #000000;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.social-btn.fb-btn {
  background: #1877f2;
}

.social-btn.line-btn {
  background: #06c755;
}

.social-btn.copy-btn {
  background: var(--bg-card);
  color: var(--text);
  border: 1px solid var(--border);
}

.social-btn.copy-btn:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
}

@media (max-width: 600px) {
  .social-share-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .social-btn {
    justify-content: center;
  }
}


/* ===== XRP SUPPORT BANNER ===== */
.xrp-banner {
  display: flex;
  align-items: center;
  gap: 28px;
  background: linear-gradient(135deg, rgba(52, 106, 169, 0.14), rgba(0, 170, 228, 0.08));
  border: 1px solid rgba(0, 170, 228, 0.22);
  border-radius: 16px;
  padding: 32px 36px;
  margin-top: 40px;
}

.xrp-banner-icon {
  font-size: 44px;
  flex-shrink: 0;
  filter: drop-shadow(0 0 16px rgba(0, 170, 228, 0.4));
}

.xrp-banner-body {
  flex: 1;
  min-width: 0;
}

.xrp-banner-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 10px;
  line-height: 1.4;
}

.xrp-banner-desc {
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.7;
  margin-bottom: 12px;
}

.xrp-banner-address {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.xrp-banner-address-label {
  font-size: 0.75rem;
  color: rgba(0, 170, 228, 0.7);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.xrp-banner-address code {
  font-size: 0.78rem;
  color: #60a5fa;
  background: rgba(96, 165, 250, 0.1);
  border: 1px solid rgba(96, 165, 250, 0.2);
  border-radius: 6px;
  padding: 3px 10px;
  letter-spacing: 0.03em;
  word-break: break-all;
}

@media (max-width: 780px) {
  .xrp-banner {
    flex-direction: column;
    text-align: center;
    padding: 24px 20px;
    gap: 16px;
  }

  .xrp-banner-icon {
    font-size: 32px;
  }

  .xrp-banner-address {
    justify-content: center;
  }
}

/* ===== Weekly Column ===== */
.column-grid {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.column-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: var(--transition);
}

.column-card:hover {
  border-color: var(--accent);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
  transform: translateY(-2px);
}

.column-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  font-family: var(--font-en);
}

.column-vol {
  color: var(--accent);
  background: rgba(220, 53, 69, 0.1);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
}

.column-date {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.column-title {
  font-size: 1.25rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
  line-height: 1.4;
}

.column-body {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ===== PAGE SUBNAV ===== */
.page-subnav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 40px;
  background: var(--surface);
  padding: 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
}

.subnav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 8px 16px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.03);
  color: var(--text-dim);
  text-decoration: none;
  transition: all 0.3s ease;
  min-width: 80px;
}

.subnav-link:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
}

.subnav-link.active {
  background: var(--accent);
  color: var(--bg);
  box-shadow: 0 4px 12px rgba(245, 166, 35, 0.3);
}

.subnav-link .ja {
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 2px;
}

.subnav-link .en {
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.7rem;
  opacity: 0.7;
}

.subnav-link.active .en,
.subnav-link.active .ja {
  opacity: 1;
}

@media (max-width: 600px) {
  .page-subnav {
    flex-wrap: nowrap;
    justify-content: flex-start;
    overflow-x: auto;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
    gap: 8px;
    padding: 10px 12px;
  }

  .page-subnav::-webkit-scrollbar {
    display: none;
  }

  .subnav-link {
    flex-shrink: 0;
    min-width: auto;
    padding: 7px 14px;
  }

  .subnav-link .en {
    display: none;
  }

  .subnav-link .ja {
    font-size: 0.88rem;
    margin-bottom: 0;
  }
}

/* ===== FAQ (practice.html) ===== */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 2.5rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.3s;
}

.faq-item.open {
  border-color: var(--accent);
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  padding: 20px 24px;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  font-family: 'Noto Sans JP', sans-serif;
  transition: color 0.2s;
}

.faq-question:hover {
  color: var(--accent);
}

.faq-icon {
  font-size: 1.5rem;
  font-weight: 300;
  color: var(--accent);
  flex-shrink: 0;
  line-height: 1;
  transition: transform 0.3s ease;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.38s ease, padding 0.38s ease;
  padding: 0 24px;
}

.faq-item.open .faq-answer {
  max-height: 400px;
  padding: 0 24px 22px;
}

.faq-answer p {
  color: var(--text-secondary);
  line-height: 1.8;
  font-size: 0.95rem;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

/* ===== SCALE & MODE REFERENCE (reference.html) ===== */
.scale-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 2.5rem;
}

.scale-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 20px;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}

.scale-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  box-shadow: var(--shadow);
}

.scale-card-header {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 10px;
}

.scale-card-name {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--accent);
}

.scale-card-alias {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.scale-card-formula {
  font-family: 'Outfit', monospace;
  font-size: 0.82rem;
  color: var(--text);
  background: rgba(255, 255, 255, 0.05);
  padding: 5px 10px;
  border-radius: 5px;
  margin-bottom: 10px;
  letter-spacing: 0.06em;
}

.scale-card-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 10px;
}

.scale-card-chords {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
}

.scale-chord-tag {
  display: inline-block;
  background: rgba(245, 166, 35, 0.12);
  color: var(--accent);
  padding: 3px 9px;
  border-radius: 20px;
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  font-size: 0.78rem;
  border: 1px solid rgba(245, 166, 35, 0.25);
}

@media (max-width: 900px) {
  .scale-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .scale-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== Column Article Body ===== */
.column-body {
  margin-top: 2.5rem;
  font-size: 1.05rem;
  line-height: 1.9;
  color: var(--text-secondary);
}

.column-body h2 {
  font-size: 1.3rem;
  color: rgba(255, 255, 255, 0.92);
  margin: 2.5rem 0 0.9rem;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 700;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid rgba(245, 166, 35, 0.25);
}

.column-tip-box {
  background: rgba(245, 166, 35, 0.05);
  border-left: 3px solid rgba(245, 166, 35, 0.55);
  border-radius: 0 8px 8px 0;
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
}

.column-tip-box strong {
  color: var(--accent);
}

/* ===== Column Article - Diagrams ===== */
.column-diagram {
  border: 1px dashed rgba(245, 166, 35, 0.3);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
  text-align: center;
  color: rgba(255, 255, 255, 0.38);
  font-size: 0.88rem;
  font-style: italic;
  background: rgba(255, 255, 255, 0.02);
  font-family: 'Outfit', sans-serif;
  line-height: 1.7;
}

.column-diagram .diagram-label {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: rgba(245, 166, 35, 0.55);
  font-style: normal;
  font-weight: 600;
}

/* SVG diagram: applied when actual diagram is embedded
   Coordinate spec (line-spacing=12px, staff-bottom-line y=80):
     Line5 y=32, Space4 y=38, Line4 y=44, Space3 y=50
     Line3 y=56, Space2 y=62, Line2 y=68, Space1 y=74
     Line1 y=80, SpaceBelow y=86, Ledger1Below y=92
   Open strings (per article): 1E=sp4, 2B=L3, 3G=L2, 4D=sp1, 5A=spBelow, 6E=Ldgr1
   Note radius=5, fill=#f5a623, staff-stroke=rgba(255,255,255,0.2) */
.column-diagram.has-svg {
  font-style: normal;
  color: var(--text-dim);
  padding: 1.25rem 1rem;
}

.column-diagram.has-svg svg {
  display: block;
  width: 100%;
  max-width: 640px;
  margin: 0.5rem auto 0;
  overflow: visible;
}

/* ===== Column Article - Checklist ===== */
.column-checklist-group {
  margin-bottom: 1.75rem;
}

.column-checklist-group h3 {
  font-size: 0.92rem;
  color: rgba(255, 255, 255, 0.78);
  margin: 0 0 0.6rem;
  font-weight: 700;
  font-family: 'Noto Sans JP', sans-serif;
  padding-left: 0;
  letter-spacing: 0.02em;
}

.column-checklist {
  list-style: none;
  padding: 0;
  margin: 0;
}

.column-checklist li {
  padding: 0.4rem 0 0.4rem 2rem;
  position: relative;
  color: var(--text-secondary);
  line-height: 1.65;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 0.93rem;
}

.column-checklist li::before {
  content: '\25A1';
  position: absolute;
  left: 0;
  color: rgba(245, 166, 35, 0.5);
  font-size: 0.95rem;
  font-style: normal;
}

/* ===== SNS Share Buttons ===== */
.share-section {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
}

.share-label {
  font-size: 0.85rem;
  color: var(--text-muted, rgba(255, 255, 255, 0.4));
  margin-bottom: 1rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-family: 'Outfit', sans-serif;
}

.share-buttons {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 10px 22px;
  border-radius: 50px;
  font-size: 0.9rem;
  font-weight: 600;
  font-family: 'Outfit', sans-serif;
  text-decoration: none;
  transition: transform 0.2s, box-shadow 0.2s, opacity 0.2s;
}

.share-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
  opacity: 0.9;
}

.share-btn svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.share-btn-x {
  background: #000;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.share-btn-line {
  background: #06C755;
  color: #fff;
}

/* ===== Related Content Block ===== */
.related-section {
  margin-top: 2.5rem;
  padding: 1.75rem 2rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: 12px;
}

.related-section-title {
  font-size: 0.8rem;
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1rem;
}

.related-links {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.related-link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text-secondary, rgba(255, 255, 255, 0.7));
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.related-link::before {
  content: '→';
  color: var(--accent);
  font-size: 0.85rem;
  flex-shrink: 0;
}

.related-link:hover {
  color: #fff;
}

@media (max-width: 600px) {
  .share-btn {
    padding: 9px 18px;
    font-size: 0.85rem;
  }

  .related-section {
    padding: 1.25rem 1.25rem;
  }
}

/* ===== SNS VIDEO EMBED ===== */
.sns-video-container {
  margin: 3rem 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 1.5rem;
  box-shadow: var(--shadow);
  transition: border-color 0.3s, box-shadow 0.3s;
}

.sns-video-container:hover {
  border-color: rgba(245, 166, 35, 0.4);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.6);
}

.sns-video-header {
  text-align: center;
  margin-bottom: 2rem;
}

.sns-video-title {
  font-size: 1.4rem;
  color: var(--accent);
  margin-bottom: 0.5rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.sns-video-desc {
  font-size: 0.95rem;
  color: var(--text-dim);
}

.sns-video-wrapper {
  width: 100%;
  max-width: 320px;
  aspect-ratio: 9 / 16;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 10px 32px rgba(0, 0, 0, 0.5);
  position: relative;
  background: #000;
}

.sns-video-wrapper iframe {
  width: 100%;
  height: 100%;
  border: none;
  position: absolute;
  top: 0;
  left: 0;
}

.sns-video-cta {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
}

.sns-video-cta p {
  font-weight: 600;
  color: var(--text);
  font-size: 1.05rem;
  margin: 0;
}

.btn-youtube {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: #FF0000;
  color: #FFF;
  padding: 14px 32px;
  border-radius: 50px;
  font-weight: 700;
  font-size: 1.1rem;
  text-decoration: none;
  transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
  letter-spacing: 0.03em;
}

.btn-youtube:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(255, 0, 0, 0.4);
  background: #CC0000;
  color: #FFF;
}

/* ===== NOTE PROMO BANNER & CTA ===== */
.note-promo-banner {
  background: linear-gradient(135deg, rgba(46, 204, 113, 0.1) 0%, rgba(22, 22, 31, 0.9) 100%);
  border: 1px solid rgba(46, 204, 113, 0.3);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  margin: 4rem 0;
  text-align: center;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
  position: relative;
  overflow: hidden;
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}

.note-promo-banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 50%;
  height: 100%;
  background: linear-gradient(to right, transparent, rgba(46, 204, 113, 0.1), transparent);
  transform: skewX(-25deg);
  animation: ad-shimmer 6s infinite;
}

.note-promo-banner:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 50px rgba(46, 204, 113, 0.15);
  border-color: rgba(46, 204, 113, 0.6);
}

.note-promo-icon {
  width: 64px;
  height: 64px;
  background: #2ECC71;
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  box-shadow: 0 0 20px rgba(46, 204, 113, 0.4);
}

.note-promo-icon svg {
  width: 32px;
  height: 32px;
}

.note-promo-title {
  font-size: 1.8rem;
  font-family: 'Outfit', sans-serif;
  font-weight: 800;
  margin-bottom: 1rem;
  color: #fff;
}

.note-promo-desc {
  font-size: 1.1rem;
  color: var(--text-dim);
  max-width: 600px;
  margin: 0 auto 2rem;
  line-height: 1.6;
}

.btn-note {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: #2ECC71;
  color: #fff !important;
  font-weight: 700;
  font-size: 1.1rem;
  padding: 16px 40px;
  border-radius: 50px;
  text-decoration: none;
  transition: background 0.3s, transform 0.3s, box-shadow 0.3s;
  letter-spacing: 0.05em;
  position: relative;
  z-index: 2;
}

.btn-note:hover {
  background: #27AE60;
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(46, 204, 113, 0.4);
}

.note-cta-block {
  margin: 4rem 0 2rem;
  padding: 2.5rem;
  background: rgba(46, 204, 113, 0.05);
  border-left: 4px solid #2ECC71;
  border-radius: 0 var(--radius) var(--radius) 0;
}

.note-cta-title {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 0.8rem;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
}

.note-cta-desc {
  font-size: 1rem;
  color: var(--text-dim);
  margin-bottom: 1.5rem;
  line-height: 1.6;
}

/* ===== LEAD MAGNET BANNER ===== */
.lead-magnet-banner {
  background: linear-gradient(135deg, #111, #1a1a1a);
  border: 1px solid rgba(232, 67, 62, 0.3);
  border-radius: var(--radius-lg);
  padding: 40px;
  display: flex;
  align-items: center;
  gap: 40px;
  margin: 60px 0;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3), inset 0 0 0 1px rgba(255, 255, 255, 0.05);
  position: relative;
  overflow: hidden;
}

.lm-content {
  flex: 1;
  position: relative;
  z-index: 2;
}

.lm-badge {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 1px;
  padding: 4px 10px;
  border-radius: 4px;
  margin-bottom: 12px;
  text-transform: uppercase;
  box-shadow: 0 2px 10px rgba(232, 67, 62, 0.4);
}

.lm-title {
  font-size: 1.8rem;
  font-weight: 900;
  color: #fff;
  margin-bottom: 12px;
  line-height: 1.3;
}

.lm-desc {
  font-size: 1rem;
  color: #bbb;
  margin-bottom: 24px;
  line-height: 1.6;
}

.lm-form {
  display: flex;
  gap: 12px;
  margin-bottom: 12px;
}

.lm-input {
  flex: 1;
  padding: 14px 20px;
  border-radius: 30px;
  border: 1px solid #333;
  background: #222;
  color: #fff;
  font-size: 1rem;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.lm-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(232, 67, 62, 0.2);
}

.lm-submit {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 14px 28px;
  border-radius: 30px;
  font-weight: bold;
  font-size: 1rem;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s, background 0.3s;
  box-shadow: 0 4px 15px rgba(232, 67, 62, 0.4);
  white-space: nowrap;
}

.lm-submit:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(232, 67, 62, 0.6);
  background: #f75550;
}

.lm-note {
  font-size: 0.8rem;
  color: #777;
  margin: 0;
}

.lm-visual {
  width: 200px;
  height: 260px;
  perspective: 1000px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.lm-book {
  width: 160px;
  height: 220px;
  position: relative;
  transform-style: preserve-3d;
  transform: rotateY(-20deg) rotateX(10deg);
  transition: transform 0.5s cubic-bezier(0.2, 0.8, 0.2, 1);
  z-index: 2;
}

.lead-magnet-banner:hover .lm-book {
  transform: rotateY(-10deg) rotateX(5deg) translateY(-5px);
}

.lm-book-cover {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #e8433e, #b82b27);
  border-radius: 4px 12px 12px 4px;
  box-shadow: inset 4px 0 10px rgba(0, 0, 0, 0.1), 5px 5px 20px rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  border-left: 2px solid rgba(255, 255, 255, 0.2);
}

.book-title {
  color: #fff;
  font-weight: 900;
  font-size: 1.4rem;
  line-height: 1.1;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  font-style: italic;
  font-family: Impact, sans-serif;
  letter-spacing: 1px;
}

.lm-book-pages {
  position: absolute;
  top: 4px;
  right: -8px;
  width: 12px;
  height: calc(100% - 8px);
  background: #eee;
  border-radius: 0 4px 4px 0;
  transform: translateZ(-10px);
  background-image: repeating-linear-gradient(to right, #ccc, #ccc 1px, #fff 1px, #fff 3px);
}

.lm-glow {
  position: absolute;
  width: 150%;
  height: 150%;
  background: radial-gradient(circle, rgba(232, 67, 62, 0.2) 0%, transparent 70%);
  top: -25%;
  left: -25%;
  z-index: 1;
  animation: pulse-glow 4s infinite alternate;
}

@keyframes pulse-glow {
  0% {
    transform: scale(1);
    opacity: 0.5;
  }

  100% {
    transform: scale(1.1);
    opacity: 0.8;
  }
}

@media (max-width: 768px) {
  .lead-magnet-banner {
    flex-direction: column-reverse;
    text-align: center;
    padding: 30px 20px;
    gap: 20px;
  }

  .lm-form {
    flex-direction: column;
  }

  .lm-visual {
    width: 160px;
    height: 200px;
  }

  .lm-book {
    width: 130px;
    height: 180px;
  }
}