/* ============================================================
   Carnatic Flute Lessons — shared stylesheet
   Used by all pages (index.html, basics.html, future lessons).
   No external dependencies (fonts/icons/images) — everything is
   drawn with CSS or inline SVG, safe for file:// and static hosting.
   ============================================================ */

:root {
  /* Warm maroon + gold palette evoking Carnatic classical music */
  --color-bg: #fbf3e6;
  --color-surface: #fffaf1;
  --color-surface-alt: #f8ecd8;
  --color-primary: #7a1f2b;      /* deep maroon */
  --color-primary-dark: #500f18; /* darker maroon, header/nav */
  --color-accent: #c9973f;       /* gold */
  --color-accent-light: #e8c77e; /* light gold */
  --color-text: #2b1810;
  --color-muted: #6b5142;
  --color-border: #e7d3ae;
  --color-sa: #7a1f2b;           /* tonic Sa highlight color */
  --radius: 12px;
  --max-width: 1040px;
  --shadow-soft: 0 2px 8px rgba(80, 15, 24, 0.08);
  --shadow-hover: 0 8px 20px rgba(80, 15, 24, 0.14);
  font-size: 16px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  background-color: var(--color-bg);
  background-image:
    radial-gradient(circle at 15% 10%, rgba(201, 151, 63, 0.10) 0, transparent 45%),
    radial-gradient(circle at 90% 0%, rgba(122, 31, 43, 0.07) 0, transparent 40%),
    repeating-linear-gradient(135deg, rgba(122, 31, 43, 0.02) 0 2px, transparent 2px 26px);
  background-attachment: fixed;
  color: var(--color-text);
  line-height: 1.65;
}

a {
  color: var(--color-primary);
}

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

svg.icon {
  width: 1em;
  height: 1em;
  display: inline-block;
  vertical-align: -0.15em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---------- Sticky top nav ---------- */

.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--color-primary-dark);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.18);
}

.site-nav .nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.6rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.site-nav .brand {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  color: #fdf3e0;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: 0.01em;
}

.site-nav .brand svg {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: var(--color-accent-light);
}

.site-nav .brand:hover {
  color: #fff;
}

.site-nav ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.25rem;
}

.site-nav a.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.15rem;
  color: #f1dcc0;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  border-bottom: 3px solid transparent;
}

.site-nav a.nav-link svg {
  color: var(--color-accent-light);
}

.site-nav a.nav-link:hover,
.site-nav a.nav-link.active {
  color: #fff;
  border-bottom-color: var(--color-accent);
}

.site-nav .nav-link.is-placeholder {
  opacity: 0.55;
  cursor: default;
}

/* ---------- Hero (index.html) ---------- */

.hero {
  background:
    linear-gradient(160deg, var(--color-primary-dark) 0%, var(--color-primary) 62%, #8a2c1f 100%);
  color: #fdf3e0;
  position: relative;
  overflow: hidden;
}

.hero .hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 1.25rem 3.5rem;
  display: flex;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

.hero .hero-text {
  flex: 1 1 320px;
  min-width: 260px;
}

.hero h1 {
  margin: 0 0 0.6rem 0;
  font-size: 2.1rem;
  line-height: 1.25;
}

.hero p.tagline {
  margin: 0;
  color: #f0d9b8;
  font-size: 1.05rem;
  max-width: 42ch;
}

.hero .hero-illustration {
  flex: 0 0 auto;
  width: 220px;
  max-width: 45vw;
  color: var(--color-accent-light);
}

.hero .hero-waves {
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 60px;
  color: var(--color-bg);
}

/* Decorative note motifs scattered in the hero */
.hero .floating-note {
  position: absolute;
  color: rgba(232, 199, 126, 0.35);
  z-index: 0;
}

/* ---------- Page header (basics.html, non-hero pages) ---------- */

.page-header {
  background: linear-gradient(120deg, var(--color-primary-dark), var(--color-primary));
  color: #fdf3e0;
}

.page-header .header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

.page-header .header-inner svg.page-icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  color: var(--color-accent-light);
}

.page-header h1 {
  margin: 0 0 0.2rem 0;
  font-size: 1.5rem;
}

.page-header p {
  margin: 0;
  color: #f0d9b8;
  font-size: 0.95rem;
}

/* ---------- Page layout with optional TOC sidebar ---------- */

.page-layout {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
  display: flex;
  align-items: flex-start;
  gap: 2rem;
}

main.no-sidebar {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
}

.lesson-content {
  flex: 1 1 auto;
  min-width: 0;
}

/* Table of contents */

.toc {
  flex: 0 0 220px;
  position: sticky;
  top: 4.5rem;
  align-self: flex-start;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.1rem;
  box-shadow: var(--shadow-soft);
}

.toc h4 {
  margin: 0 0 0.6rem 0;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-muted);
}

.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.toc a {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  text-decoration: none;
  color: var(--color-text);
  font-size: 0.88rem;
  padding: 0.25rem 0.35rem;
  border-radius: 6px;
}

.toc a svg {
  color: var(--color-primary);
  flex-shrink: 0;
}

.toc a:hover {
  background: var(--color-surface-alt);
  color: var(--color-primary);
}

/* Collapsible TOC toggle, shown only on mobile */
.toc-toggle {
  display: none;
}

/* ---------- Footer ---------- */

footer.site-footer {
  text-align: center;
  padding: 2rem 1.25rem;
  color: var(--color-muted);
  font-size: 0.85rem;
}

footer.site-footer svg {
  color: var(--color-accent);
  margin-bottom: 0.4rem;
}

/* ---------- Cards (used on the index/landing page) ---------- */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
  margin: 1.5rem 0;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.4rem;
  text-decoration: none;
  color: var(--color-text);
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  box-shadow: var(--shadow-soft);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.card .card-icon {
  width: 42px;
  height: 42px;
  color: var(--color-primary);
  background: var(--color-surface-alt);
  border-radius: 50%;
  padding: 8px;
}

.card h3 {
  margin: 0;
  color: var(--color-primary);
  font-size: 1.15rem;
}

.card p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.92rem;
  flex: 1 1 auto;
}

.card .tag {
  display: inline-block;
  margin-top: 0.2rem;
  font-size: 0.75rem;
  background: var(--color-accent);
  color: #fff;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  align-self: flex-start;
}

.card .btn-start {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  align-self: flex-start;
  margin-top: 0.4rem;
  background: var(--color-primary);
  color: #fff;
  padding: 0.5rem 1rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.88rem;
  text-decoration: none;
}

.card .btn-start:hover {
  background: var(--color-primary-dark);
}

.card.card-disabled {
  opacity: 0.6;
  cursor: default;
}

.card.card-disabled:hover {
  transform: none;
  box-shadow: var(--shadow-soft);
}

/* ---------- Section styling ---------- */

section.lesson-section {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.4rem 1.6rem;
  margin: 1.75rem 0;
  box-shadow: var(--shadow-soft);
  scroll-margin-top: 4.5rem;
}

section.lesson-section h2 {
  color: var(--color-primary);
  border-bottom: 2px solid var(--color-border);
  padding-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

section.lesson-section h2 svg {
  color: var(--color-accent);
  width: 1.3rem;
  height: 1.3rem;
  flex-shrink: 0;
}

section.lesson-section h3 {
  color: var(--color-primary-dark);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

section.lesson-section h3 svg {
  width: 1.05rem;
  height: 1.05rem;
  color: var(--color-accent);
  flex-shrink: 0;
}

.raga-name {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-style: normal;
  font-weight: 600;
  color: var(--color-primary-dark);
}

.raga-name svg {
  width: 0.95em;
  height: 0.95em;
  color: var(--color-accent);
}

.note {
  background: var(--color-surface-alt);
  border-left: 4px solid var(--color-accent);
  padding: 0.7rem 1rem;
  border-radius: 4px;
  font-size: 0.92rem;
  margin: 1rem 0;
}

/* ---------- Swara notation tables/blocks ---------- */

.notation-card {
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  border-radius: 8px;
  padding: 0.9rem 1rem 1rem;
  margin: 0.9rem 0 1.25rem;
}

.notation-card .notation-caption {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-weight: 600;
  color: var(--color-muted);
  margin: 0 0 0.5rem 0;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.notation, .notation table {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

table.swara-table {
  border-collapse: collapse;
  width: 100%;
  margin: 0;
  font-size: 0.95rem;
  background: var(--color-surface);
}

table.swara-table caption {
  text-align: left;
  font-weight: 600;
  color: var(--color-muted);
  margin-bottom: 0.35rem;
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
}

table.swara-table th,
table.swara-table td {
  border: 1px solid var(--color-border);
  padding: 0.4rem 0.6rem;
  text-align: center;
}

table.swara-table th {
  background: var(--color-primary);
  color: #fdf3e0;
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
}

table.swara-table td.sa {
  color: var(--color-sa);
  font-weight: 700;
  background: #f6e6cf;
}

table.swara-table td.sahitya {
  color: var(--color-muted);
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-style: italic;
}

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

/* ---------- Fingering diagrams ---------- */

.fingering-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 1rem;
  margin: 1rem 0 1.5rem;
}

.fingering-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.9rem 0.75rem 1rem;
  text-align: center;
  box-shadow: var(--shadow-soft);
}

.fingering-card .note-name {
  font-weight: 700;
  color: var(--color-primary);
  font-size: 1.1rem;
  margin-bottom: 0.4rem;
}

.fingering-card svg.fingering-svg {
  width: 100%;
  height: auto;
  color: var(--color-primary-dark);
  margin-bottom: 0.5rem;
}

.fingering-card .fingering-cue {
  font-size: 0.8rem;
  color: var(--color-muted);
  margin: 0;
}

.fingering-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  align-items: center;
  font-size: 0.85rem;
  color: var(--color-muted);
  margin: 0.75rem 0 0;
}

.fingering-legend .legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.fingering-legend svg {
  width: 1rem;
  height: 1rem;
  color: var(--color-primary-dark);
}

/* ---------- Daily long note (Sa Sadhana) practice ---------- */

.routine-card {
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius);
  padding: 1.1rem 1.3rem;
  margin: 1rem 0 1.5rem;
}

.routine-card h4 {
  margin: 0 0 0.6rem 0;
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.routine-card h4 svg {
  color: var(--color-accent);
  width: 1.1rem;
  height: 1.1rem;
}

.routine-card ol {
  margin: 0 0 0.75rem 0;
  padding-left: 1.25rem;
}

.tip-box {
  background: #f6e6cf;
  border: 1px dashed var(--color-accent);
  border-radius: 8px;
  padding: 0.7rem 1rem;
  font-size: 0.9rem;
  margin: 0.75rem 0 0;
  display: flex;
  gap: 0.6rem;
  align-items: flex-start;
}

.tip-box svg {
  flex-shrink: 0;
  width: 1.2rem;
  height: 1.2rem;
  color: var(--color-primary);
  margin-top: 0.1rem;
}

/* Simple long-note count-up timer */

.long-note-timer {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin: 1rem 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  box-shadow: var(--shadow-soft);
}

.long-note-timer .timer-display {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  min-width: 4.5ch;
  text-align: center;
}

.long-note-timer .timer-targets {
  font-size: 0.82rem;
  color: var(--color-muted);
  flex: 1 1 160px;
}

.long-note-timer .buttons {
  display: flex;
  gap: 0.6rem;
}

.long-note-timer button {
  font: inherit;
  padding: 0.5rem 1.1rem;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.long-note-timer button svg {
  width: 0.9rem;
  height: 0.9rem;
}

.long-note-timer .btn-start {
  background: var(--color-primary);
  color: #fff;
}

.long-note-timer .btn-start:hover {
  background: var(--color-primary-dark);
}

.long-note-timer .btn-reset {
  background: var(--color-border);
  color: var(--color-text);
}

.long-note-timer .btn-reset:hover {
  background: #d9c090;
}

/* ---------- Practice checklist table ---------- */

table.checklist-table {
  border-collapse: collapse;
  width: 100%;
  margin: 0.75rem 0;
}

table.checklist-table th,
table.checklist-table td {
  border: 1px solid var(--color-border);
  padding: 0.5rem 0.7rem;
  text-align: left;
}

table.checklist-table th {
  background: var(--color-primary);
  color: #fdf3e0;
}

table.checklist-table tr:nth-child(even) {
  background: var(--color-surface-alt);
}

/* ---------- Tala metronome widget ---------- */

.tala-player {
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  border-top: 4px solid var(--color-primary);
  border-radius: var(--radius);
  padding: 1.1rem 1.3rem;
  margin: 1rem 0 1.5rem;
  box-shadow: var(--shadow-soft);
}

.tala-player h4 {
  margin: 0 0 0.85rem 0;
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.tala-player h4 svg {
  color: var(--color-accent);
  width: 1.15rem;
  height: 1.15rem;
}

.tala-player .controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  align-items: center;
  margin-bottom: 0.9rem;
}

.tala-player label {
  font-size: 0.85rem;
  color: var(--color-muted);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.tala-player select,
.tala-player input[type="text"],
.tala-player input[type="number"] {
  font: inherit;
  padding: 0.35rem 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
}

.tala-player input[type="range"] {
  width: 140px;
  accent-color: var(--color-primary);
}

.tala-player .bpm-value {
  font-weight: 600;
  color: var(--color-primary-dark);
}

.tala-player .buttons {
  display: flex;
  gap: 0.6rem;
}

.tala-player button {
  font: inherit;
  padding: 0.5rem 1.1rem;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.tala-player button svg {
  width: 0.95rem;
  height: 0.95rem;
}

.tala-player .btn-play {
  background: var(--color-primary);
  color: #fff;
}

.tala-player .btn-play:hover:not(:disabled) {
  background: var(--color-primary-dark);
}

.tala-player .btn-stop {
  background: var(--color-border);
  color: var(--color-text);
}

.tala-player .btn-stop:hover:not(:disabled) {
  background: #d9c090;
}

.tala-player button:disabled {
  opacity: 0.5;
  cursor: default;
}

.tala-player .custom-pattern-field {
  display: none;
}

.tala-player.custom-mode .custom-pattern-field {
  display: flex;
}

.beat-display {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 1.3rem;
  letter-spacing: 0.15em;
  display: flex;
  flex-wrap: wrap;
  gap: 0.3em;
}

.beat-display .beat {
  padding: 0.15em 0.35em;
  border-radius: 6px;
  color: var(--color-muted);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
}

.beat-display .beat.group-start {
  font-weight: 700;
  color: var(--color-primary-dark);
  border-color: var(--color-accent);
}

.beat-display .beat.active {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

.beat-display .group-sep {
  color: var(--color-border);
  padding: 0 0.1em;
}

.anchor-target {
  scroll-margin-top: 4.5rem;
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .page-layout {
    flex-direction: column;
  }

  .toc {
    position: static;
    width: 100%;
    flex: 1 1 auto;
  }

  .toc ul {
    display: none;
  }

  .toc.open ul {
    display: flex;
  }

  .toc-toggle {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    width: 100%;
    background: none;
    border: none;
    padding: 0;
    font: inherit;
    font-weight: 700;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-muted);
    cursor: pointer;
  }

  .toc-toggle svg {
    transition: transform 0.15s ease;
  }

  .toc.open .toc-toggle svg {
    transform: rotate(180deg);
  }

  .toc h4 {
    display: none;
  }
}

@media (max-width: 600px) {
  :root {
    font-size: 15px;
  }

  .hero .hero-inner {
    padding: 2.25rem 1.25rem 2.75rem;
  }

  .hero h1 {
    font-size: 1.65rem;
  }

  .hero .hero-illustration {
    width: 150px;
  }

  section.lesson-section {
    padding: 1.1rem;
  }

  .tala-player .controls {
    gap: 0.6rem 1rem;
  }
}