:root {
  /* Saimai Classroom palette — inspired by Thai flag + temple gold */
  --bg: #ffffff;             /* clean white */
  --bg-soft: #f5f6f8;        /* subtle band */
  --surface: #ffffff;        /* card */
  --surface-2: #fafbfd;
  --text: #15192a;           /* body — high contrast */
  --muted: #4a5163;          /* secondary text — readable */
  --thai-red: #c8233c;       /* primary, softened Thai red */
  --thai-red-dark: #a51931;
  --thai-navy: #2e3a6b;      /* secondary, softened Thai blue */
  --thai-navy-dark: #1f2952;
  --gold: #e8a33d;           /* temple gold accent */
  --jade: #3fa796;           /* success / highlight */
  --card-border: rgba(46, 58, 107, 0.14);
  --card-shadow: 0 6px 18px rgba(31, 41, 82, 0.08);
  --card-shadow-hover: 0 12px 28px rgba(31, 41, 82, 0.14);
}

[data-theme="dark"] {
  --bg: #0f1320;
  --bg-soft: #161b2c;
  --surface: #1a2032;
  --surface-2: #20283e;
  --text: #e8ecf5;
  --muted: #a4adc2;
  --thai-red: #ff5c75;
  --thai-red-dark: #e83e5b;
  --thai-navy: #8aa0e0;       /* lifted for contrast on dark */
  --thai-navy-dark: #6b85d1;
  --gold: #f0b860;
  --jade: #5cc4b3;
  --card-border: rgba(255, 255, 255, 0.10);
  --card-shadow: 0 6px 18px rgba(0, 0, 0, 0.35);
  --card-shadow-hover: 0 12px 28px rgba(0, 0, 0, 0.5);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Space Grotesk", sans-serif;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  overflow-x: hidden;
}

/* Decorative blobs hidden — keep markup compatible but invisible */
.aurora {
  display: none;
}

.hero {
  padding: 0.75rem 6vw 1.5rem;
  background: var(--surface);
  border-bottom: 1px solid var(--card-border);
  position: relative;
}

/* Thin Thai-flag accent line along the top */
.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(
    90deg,
    var(--thai-red) 0 25%,
    #ffffff 25% 35%,
    var(--thai-navy) 35% 65%,
    #ffffff 65% 75%,
    var(--thai-red) 75% 100%
  );
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-actions {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.brand {
  font-family: "Orbitron", sans-serif;
  letter-spacing: 1px;
  font-size: 1rem;
  color: var(--gold);
  font-weight: 700;
}

.brand-link {
  color: inherit;
  text-decoration: none;
  display: inline-block;
  background: linear-gradient(
    180deg,
    var(--thai-red) 0 16%,
    #ffffff 16% 27%,
    var(--thai-navy-dark) 27% 73%,
    #ffffff 73% 84%,
    var(--thai-red) 84% 100%
  );
  border: 1px solid rgba(31, 41, 82, 0.5);
  border-radius: 999px;
  padding: 0.5rem 1rem;
  line-height: 1;
  text-shadow: 0 1px 1px rgba(0, 0, 0, 0.22);
  box-shadow: 0 7px 16px rgba(31, 41, 82, 0.22);
}

.brand-link:hover {
  filter: brightness(1.03);
}

.cta-small {
  text-decoration: none;
  color: var(--thai-navy);
  background: var(--surface);
  border: 1px solid var(--card-border);
  padding: 0.5rem 0.95rem;
  border-radius: 999px;
  font-weight: 600;
  transition: 0.2s ease;
}

.cta-small:hover {
  border-color: var(--thai-red);
  color: var(--thai-red);
  box-shadow: 0 4px 12px rgba(200, 35, 60, 0.15);
}

.cta-small.active {
  background: var(--thai-navy);
  border-color: var(--thai-navy);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(46, 58, 107, 0.25);
}

.theme-toggle {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: 50%;
  border: 1px solid var(--card-border);
  background: var(--surface);
  color: var(--thai-navy);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--thai-red);
  color: var(--thai-red);
}

[data-theme="dark"] .theme-toggle {
  color: var(--gold);
}

.hero-compact {
  padding-bottom: 1rem;
}

.hero-compact .hero-content {
  margin-top: 1rem;
}

.hero-content {
  max-width: 760px;
  margin-top: 1.25rem;
  animation: rise 0.8s ease;
}

.kicker {
  color: var(--gold);
  font-family: "Orbitron", sans-serif;
  letter-spacing: 2px;
  font-size: 0.72rem;
  margin-bottom: 0.35rem;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin-top: 0;
  color: var(--thai-navy);
}

h1 {
  font-family: "Orbitron", sans-serif;
  font-size: clamp(1.4rem, 3.2vw, 2.2rem);
  line-height: 1.15;
  margin-bottom: 0.5rem;
}

h2 {
  font-size: 1.5rem;
  border-left: 4px solid var(--thai-red);
  padding-left: 0.7rem;
}

h3 {
  font-size: 1.1rem;
}

.subtitle,
.section-lead {
  color: var(--muted);
  line-height: 1.6;
}

.subtitle {
  font-size: 0.95rem;
  margin: 0.25rem 0 0;
}

.hero-actions {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 0.9rem;
}

.btn {
  text-decoration: none;
  border-radius: 999px;
  padding: 0.75rem 1.2rem;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: inline-block;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: var(--thai-red);
  color: #ffffff;
  box-shadow: 0 8px 20px rgba(200, 35, 60, 0.3);
}

.btn-primary:hover {
  background: var(--thai-red-dark);
}

.btn-secondary {
  color: var(--thai-navy);
  background: var(--surface);
  border: 1px solid var(--thai-navy);
}

.btn-secondary:hover {
  background: var(--thai-navy);
  color: #ffffff;
}

main {
  padding: 0 6vw 5rem;
}

.section {
  margin-top: 2.5rem;
}

.grid {
  display: grid;
  gap: 1.1rem;
}

.modules-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin-top: 1.4rem;
}

.module-link {
  display: inline-block;
  margin-top: 0.6rem;
  color: var(--thai-red);
  text-decoration: none;
  font-weight: 700;
}

.module-link:hover {
  color: var(--thai-red-dark);
  text-decoration: underline;
}

/* Cards: clean white "notebook" surfaces */
.card {
  background: var(--surface);
  border: 1px solid var(--card-border);
  border-radius: 14px;
  padding: 1.2rem 1.3rem;
  box-shadow: var(--card-shadow);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.card:hover {
  box-shadow: var(--card-shadow-hover);
}

.card ul {
  padding-left: 1.1rem;
  color: var(--text);
  line-height: 1.7;
}

/* Color-coded top borders for module cards (kept class names) */
.glow-cyan {
  border-top: 4px solid var(--thai-navy);
}

.glow-pink {
  border-top: 4px solid var(--thai-red);
}

.glow-lime {
  border-top: 4px solid var(--gold);
}

.glow-cyan:hover { box-shadow: 0 12px 24px rgba(46, 58, 107, 0.18); }
.glow-pink:hover { box-shadow: 0 12px 24px rgba(200, 35, 60, 0.18); }
.glow-lime:hover { box-shadow: 0 12px 24px rgba(232, 163, 61, 0.22); }

.split {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1.1rem;
  align-items: start;
}

.chips {
  display: grid;
  gap: 0.7rem;
  margin-top: 1rem;
}

.chips span {
  display: block;
  background: var(--surface);
  border: 1px solid var(--card-border);
  border-left: 3px solid var(--gold);
  border-radius: 8px;
  padding: 0.7rem 0.95rem;
  color: var(--text);
}

.practice-panel {
  position: relative;
  background: linear-gradient(165deg, #ffffff, var(--surface-2));
}

.speak-btn {
  width: 100%;
  margin-top: 0.6rem;
  border: 1px solid var(--thai-navy);
  background: var(--surface);
  color: var(--thai-navy);
  padding: 0.65rem 0.8rem;
  border-radius: 10px;
  cursor: pointer;
  font-family: inherit;
  font-weight: 600;
  transition: 0.2s ease;
}

.speak-btn:hover {
  background: var(--thai-navy);
  color: #ffffff;
}

.phrase-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin-top: 1rem;
}

.phrase-card {
  border-left: 4px solid var(--jade);
}

.hidden {
  display: none;
}

.alphabet-lab {
  animation: rise 0.55s ease;
}

.alphabet-layout {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1.1rem;
  align-items: start;
}

.alphabet-panel h3,
.alphabet-side h3 {
  margin-bottom: 0.7rem;
}

.vowel-heading {
  margin: 0.4rem 0 0.5rem;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--muted);
}

.vowel-note {
  margin: 0 0 0.9rem;
  padding: 0.6rem 0.8rem;
  background: var(--bg-soft);
  border-left: 3px solid var(--gold);
  border-radius: 6px;
  color: var(--text);
  font-size: 0.9rem;
  line-height: 1.5;
}

.alphabet-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(82px, 1fr));
  gap: 0.55rem;
  margin-bottom: 1.2rem;
}

.alphabet-tile {
  border: 1px solid var(--card-border);
  background: var(--surface);
  border-radius: 10px;
  color: var(--text);
  min-height: 86px;
  padding: 0.45rem;
  cursor: pointer;
  display: grid;
  gap: 0.18rem;
  align-content: center;
  transition: 0.18s ease;
  font-family: inherit;
}

.alphabet-tile:hover {
  transform: translateY(-2px);
  border-color: var(--thai-navy);
  box-shadow: 0 6px 14px rgba(46, 58, 107, 0.18);
}

.alphabet-tile.active {
  border-color: var(--thai-red);
  background: var(--surface-2);
  box-shadow: 0 0 0 2px rgba(200, 35, 60, 0.25);
}

.alphabet-tile .tile-char {
  font-size: 1.65rem;
  font-weight: 700;
  line-height: 1;
  color: var(--thai-navy);
}

.alphabet-tile.active .tile-char {
  color: var(--thai-red);
}

.alphabet-tile .tile-name {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--thai-navy);
  letter-spacing: 0.3px;
}

.alphabet-tile .tile-pron {
  font-size: 0.68rem;
  color: var(--muted);
  font-style: italic;
}

.letter-spotlight {
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 1rem;
  background: linear-gradient(165deg, #ffffff, var(--surface-2));
  text-align: center;
}

.thai-char {
  display: block;
  font-size: 3.2rem;
  line-height: 1;
  color: var(--thai-red);
  font-weight: 700;
}

.spotlight-name {
  margin: 0.5rem 0 0;
  color: var(--thai-navy);
  font-weight: 600;
}

.audio-note {
  color: var(--jade);
  font-size: 0.88rem;
  margin-top: 0.6rem;
  font-style: italic;
}

.quiz-prompt {
  color: var(--text);
  font-weight: 500;
}

.quiz-form {
  display: grid;
  gap: 0.55rem;
}

.quiz-form label {
  font-size: 0.85rem;
  color: var(--muted);
  font-weight: 600;
}

.quiz-form input {
  border: 1px solid var(--card-border);
  background: var(--surface);
  color: var(--text);
  padding: 0.6rem 0.75rem;
  border-radius: 8px;
  font-family: inherit;
  font-size: 1.1rem;
}

.quiz-form input:focus {
  outline: none;
  border-color: var(--thai-navy);
  box-shadow: 0 0 0 3px rgba(46, 58, 107, 0.18);
}

.quiz-actions {
  display: flex;
  gap: 0.6rem;
}

.quiz-btn {
  border: 0;
  cursor: pointer;
}

.quiz-feedback {
  min-height: 1.2rem;
  font-weight: 700;
}

.quiz-feedback.good {
  color: var(--jade);
}

.quiz-feedback.bad {
  color: var(--thai-red);
}

.quiz-score {
  color: var(--muted);
  font-size: 0.92rem;
}

.footer {
  border-top: 1px solid var(--card-border);
  margin-top: 2rem;
  padding: 1.4rem 6vw 2rem;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  color: var(--muted);
  background: var(--bg-soft);
}

.footer a {
  color: var(--thai-red);
  font-weight: 600;
}

@keyframes rise {
  from {
    transform: translateY(16px);
    opacity: 0;
  }

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

@keyframes drift {
  from {
    transform: translate3d(0, 0, 0) scale(1);
  }

  to {
    transform: translate3d(25px, 40px, 0) scale(1.12);
  }
}

@media (max-width: 880px) {
  .split {
    grid-template-columns: 1fr;
  }

  .alphabet-layout {
    grid-template-columns: 1fr;
  }

  .nav {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }

  .brand {
    text-align: center;
    font-size: 0.92rem;
  }

  .nav-actions {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.45rem;
    align-items: stretch;
  }

  .cta-small {
    text-align: center;
    padding: 0.5rem 0.4rem;
    font-size: 0.78rem;
    line-height: 1.2;
  }

  .theme-toggle {
    justify-self: center;
  }

  .hero {
    padding-top: 1.4rem;
  }

  h1 {
    font-size: clamp(1.8rem, 9vw, 3rem);
  }
}

@media (max-width: 520px) {
  .nav-actions {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* --- About page --- */
.about-layout {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1.4rem;
  align-items: start;
}

.about-card {
  line-height: 1.7;
}

.about-card h2 {
  font-size: 1.4rem;
  border-left: none;
  padding-left: 0;
  margin-bottom: 0.6rem;
}

.about-card h3 {
  margin-top: 1.4rem;
  color: var(--thai-red);
}

.about-card p {
  color: var(--text);
}

.about-card ul {
  padding-left: 1.2rem;
  line-height: 1.75;
}

.signature {
  margin-top: 1.4rem;
  padding-top: 1rem;
  border-top: 1px solid var(--card-border);
  font-style: italic;
  color: var(--muted);
}

.signature strong {
  color: var(--thai-navy);
  font-style: normal;
}

.about-gallery {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.7rem;
}

.about-photo {
  margin: 0;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--card-border);
  background: var(--surface);
  box-shadow: var(--card-shadow);
  aspect-ratio: 1 / 1;
}

.about-photo-main {
  grid-column: 1 / -1;
  aspect-ratio: 4 / 5;
}

.about-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* --- Tones page --- */
.tones-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(260px, 1fr));
  gap: 1.1rem;
}

.tone-note {
  margin-top: 0.8rem;
  padding: 0.65rem 0.8rem;
  border-left: 3px solid var(--gold);
  background: var(--bg-soft);
  border-radius: 7px;
  line-height: 1.55;
}

.tone-table-wrap {
  overflow-x: auto;
}

.tone-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 0.3rem;
}

.tone-table th,
.tone-table td {
  border: 1px solid var(--card-border);
  padding: 0.55rem 0.65rem;
  text-align: left;
}

.tone-table th {
  color: var(--thai-navy);
  background: var(--bg-soft);
}

.tone-practice {
  grid-column: 1 / -1;
}

/* --- Word building page --- */
.word-build-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(260px, 1fr));
  gap: 1.1rem;
}

.thai-line {
  font-size: 1.4rem;
  color: var(--thai-red);
  letter-spacing: 0.4px;
  margin: 0.7rem 0 0.2rem;
}

.formula-box {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-top: 0.45rem;
}

.formula-box span {
  border: 1px solid var(--card-border);
  border-radius: 999px;
  padding: 0.35rem 0.65rem;
  background: var(--surface-2);
  color: var(--text);
  font-size: 0.9rem;
}

.piece-list {
  display: grid;
  gap: 0.45rem;
}

.word-piece {
  border: 1px solid var(--card-border);
  border-left: 3px solid var(--thai-navy);
  background: var(--surface);
  border-radius: 9px;
  padding: 0.55rem 0.7rem;
}

.segment-row {
  display: grid;
  gap: 0.5rem;
}

@media (max-width: 880px) {
  .about-layout {
    grid-template-columns: 1fr;
  }

  .tones-grid,
  .word-build-grid {
    grid-template-columns: 1fr;
  }
}