/* ============================================================
   LEARN — Curso de Teoría Musical
   Usa variables y base de style.css. Estética oscura del home.
   ============================================================ */

.learn-body { overflow: auto; height: auto; min-height: 100vh; }

#learn-app {
  display: flex; flex-direction: column;
  min-height: 100vh;
}

#learn-header {
  display: flex; flex-direction: column; gap: 8px;
  padding: 14px 24px 12px;
  background: var(--bg);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(12px);
}
#learn-header #header-top {
  display: flex; align-items: center; justify-content: space-between;
}
#learn-header h1 {
  font-size: 15px; font-weight: 600; letter-spacing: 0.4px;
  display: flex; align-items: center; gap: 8px;
}
.site-title-link {
  color: var(--text); text-decoration: none;
  transition: color 0.2s;
}
.site-title-link:hover { color: #fff; }
.title-sep { color: var(--text-muted); font-weight: 400; }
.title-section {
  color: var(--major);
  font-weight: 500;
}
.header-left {
  display: flex; align-items: center; gap: 10px;
}
.back-link {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  padding: 4px 10px;
  border-color: rgba(232,67,147,0.3);
  color: var(--major);
  min-width: 32px;
}
.back-link:hover {
  background: rgba(232,67,147,0.1);
  border-color: rgba(232,67,147,0.5);
  color: #fff;
}
.header-actions { display: flex; gap: 6px; align-items: center; position: relative; }
.header-actions a, .header-actions button {
  text-decoration: none; display: inline-block;
  font-size: 11px;
}

/* Language selector */
#lang-selector { position: relative; }
#lang-selector #lang-toggle { font-size: 11px; padding: 4px 10px; }
.lang-dropdown {
  position: absolute; top: 100%; right: 0; margin-top: 4px;
  background: rgba(20,20,20,0.95); border: 1px solid rgba(255,255,255,0.15);
  border-radius: 10px; padding: 4px;
  backdrop-filter: blur(12px); z-index: 200;
  min-width: 130px; box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}
.lang-dropdown.hidden { display: none; }
.lang-option {
  display: block; width: 100%;
  background: none; border: none; color: var(--text-muted);
  padding: 6px 12px; font-size: 12px; font-family: inherit;
  cursor: pointer; border-radius: 6px; text-align: left;
  transition: background 0.15s, color 0.15s;
}
.lang-option:hover { background: rgba(255,255,255,0.08); color: var(--text); }
.lang-option.active { background: rgba(255,255,255,0.12); color: #fff; font-weight: 600; }

/* Banner idioma no traducido */
.lang-banner {
  background: rgba(253,203,110,0.08);
  border: 1px solid rgba(253,203,110,0.2);
  color: var(--dom7);
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 12px;
  margin-bottom: 18px;
  line-height: 1.5;
}

/* Key selector */
.key-selector {
  display: flex; align-items: center; gap: 10px;
  background: rgba(20,20,20,0.6);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 10px;
  padding: 10px 14px;
  margin: 14px 0 18px;
}
.key-selector label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  font-weight: 600;
}
.key-select {
  background: rgba(10,10,10,0.8);
  border: 1px solid rgba(255,255,255,0.12);
  color: var(--text);
  padding: 6px 10px;
  border-radius: 8px;
  font-family: inherit;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  outline: none;
  transition: border-color 0.15s;
}
.key-select:hover, .key-select:focus { border-color: var(--major); color: #fff; }
.key-select option { background: #1a1a1a; color: var(--text); }
.key-selector-hint {
  font-size: 10px;
  color: var(--text-muted);
  margin-left: auto;
  font-style: italic;
}

/* Hover-playable elements */
[data-chord] {
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s, background 0.15s;
  position: relative;
}
[data-chord]:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(232,67,147,0.15);
}
[data-chord]:active { transform: translateY(0) scale(0.97); }
[data-chord].playing {
  box-shadow: 0 0 0 2px var(--major), 0 4px 20px rgba(232,67,147,0.35);
}
body.autoplay-on [data-chord]::after {
  content: '▸';
  position: absolute;
  top: 4px; right: 6px;
  font-size: 9px;
  color: var(--major);
  opacity: 0;
  transition: opacity 0.2s;
}
body.autoplay-on [data-chord]:hover::after { opacity: 0.7; }

/* Main content area */
#learn-main {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  grid-template-rows: 1fr auto;
  gap: 0;
  flex: 1;
  max-width: 1280px;
  width: 100%;
  margin: 0 auto;
  padding: 24px;
  gap: 24px;
}

#lesson-sidebar {
  grid-row: 1 / 2;
  grid-column: 1 / 2;
  position: sticky;
  top: 140px;
  align-self: start;
  max-height: calc(100vh - 160px);
  overflow-y: auto;
  padding: 16px;
  background: rgba(20,20,20,0.5);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 12px;
}
.sidebar-title {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  margin-bottom: 10px;
}
#sidebar-list {
  list-style: none; padding: 0; margin: 0;
  counter-reset: lesson;
}
#sidebar-list li {
  counter-increment: lesson;
  padding: 6px 10px;
  font-size: 12px;
  color: var(--text-muted);
  cursor: pointer;
  border-radius: 6px;
  border-left: 2px solid transparent;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
  line-height: 1.4;
}
#sidebar-list li::before {
  content: counter(lesson) ".";
  display: inline-block;
  width: 1.6em;
  color: rgba(255,255,255,0.25);
  font-variant-numeric: tabular-nums;
}
#sidebar-list li:hover {
  background: rgba(255,255,255,0.04);
  color: var(--text);
}
#sidebar-list li.active {
  color: #fff;
  background: rgba(232,67,147,0.08);
  border-left-color: var(--major);
}

/* Article */
#lesson-content {
  grid-row: 1 / 2;
  grid-column: 2 / 3;
  max-width: 820px;
  width: 100%;
  min-width: 0;
  padding: 8px 0 40px;
}
#lesson-content .lesson-eyebrow {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--major);
  margin-bottom: 8px;
}
#lesson-content h2 {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.2px;
  margin-bottom: 8px;
  color: #fff;
}
#lesson-content .lesson-summary {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 28px;
  line-height: 1.6;
}
#lesson-content h3 {
  font-size: 17px;
  font-weight: 600;
  color: #fff;
  margin-top: 32px;
  margin-bottom: 10px;
  letter-spacing: -0.1px;
}
#lesson-content h4 {
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-top: 18px;
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
}
#lesson-content p {
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
  margin-bottom: 14px;
}
#lesson-content ul, #lesson-content ol {
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
  padding-left: 22px;
  margin-bottom: 14px;
}
#lesson-content li { margin-bottom: 4px; }
#lesson-content strong { color: #fff; font-weight: 600; }
#lesson-content em { color: var(--dom7); font-style: normal; font-weight: 500; }
#lesson-content code {
  font-family: 'SFMono-Regular', Consolas, monospace;
  background: rgba(255,255,255,0.06);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 12px;
  color: var(--minor);
}
#lesson-content blockquote {
  border-left: 2px solid var(--major);
  background: rgba(232,67,147,0.04);
  padding: 10px 16px;
  margin: 16px 0;
  border-radius: 0 6px 6px 0;
  color: var(--text);
  font-size: 13px;
  line-height: 1.6;
}
#lesson-content blockquote strong { color: var(--major); }

/* Visual blocks */
.visual {
  background: rgba(20,20,20,0.6);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 12px;
  padding: 18px;
  margin: 18px 0;
}
.visual-caption {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 10px;
  text-align: center;
  letter-spacing: 0.3px;
}
.visual-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  margin-bottom: 10px;
}

/* Piano */
.piano-wrap { display: flex; justify-content: center; }
.piano {
  position: relative;
  display: inline-block;
  height: 120px;
  user-select: none;
}
.piano .key {
  position: absolute;
  border: 1px solid rgba(0,0,0,0.4);
  border-top: none;
  box-sizing: border-box;
  transition: background 0.2s;
}
.piano .key.white {
  background: #f5f5f5;
  width: 34px;
  height: 120px;
  border-radius: 0 0 4px 4px;
  z-index: 1;
}
.piano .key.black {
  background: #1a1a1a;
  width: 20px;
  height: 76px;
  z-index: 2;
  border-radius: 0 0 3px 3px;
}
/* Las teclas conservan su color base (blanco/negro). El rol se indica
   con un punto sobrio en la parte superior. Por defecto todas las notas
   resaltadas usan el mismo tono neutro; sólo se diferencian colores
   cuando hay que distinguir roles (root vs 3ª vs 5ª en un acorde). */
.piano .key.labeled.white { background: #f5f5f5; }
.piano .key.labeled.black { background: #1a1a1a; }
.piano .key.labeled .key-label { opacity: 0.85; }

.piano .key.highlighted::before,
.piano .key.root::before,
.piano .key.third::before,
.piano .key.fifth::before {
  content: '';
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #3b82c4;
  pointer-events: none;
}
.piano .key.black.highlighted::before,
.piano .key.black.root::before,
.piano .key.black.third::before,
.piano .key.black.fifth::before {
  background: #6ab0e8;
}
/* Tónica: punto relleno y más oscuro/claro según fondo, mismo tamaño y posición. */
.piano .key.root::before { background: #1e3a5f; }
.piano .key.black.root::before { background: #ffffff; }
/* 3ª y 5ª sólo se diferencian cromáticamente cuando se muestran junto a la tónica. */
.piano .key.third::before { background: #6b8a9a; }
.piano .key.black.third::before { background: #9bbacb; }
.piano .key.fifth::before { background: #9a8a6b; }
.piano .key.black.fifth::before { background: #cbb89b; }
.piano .key-label {
  position: absolute;
  bottom: 6px; left: 0; right: 0;
  text-align: center;
  font-size: 9px;
  color: #1a1a1a;
  font-weight: 600;
  pointer-events: none;
}
.piano .key.black .key-label {
  color: #fff; bottom: 4px; font-size: 8px;
}

/* Note circle (chromatic clock) */
.note-circle-svg { display: block; margin: 0 auto; }
.nc-segment {
  fill: rgba(255,255,255,0.02);
  stroke: rgba(255,255,255,0.08);
  stroke-width: 1;
  transition: fill 0.2s;
}
.nc-segment.highlight { fill: rgba(232,67,147,0.35); stroke: var(--major); }
.nc-segment.highlight-second { fill: rgba(0,206,201,0.3); stroke: var(--minor); }
.nc-segment.highlight-third { fill: rgba(253,203,110,0.3); stroke: var(--dom7); }
.nc-label {
  font-size: 12px; font-weight: 600;
  fill: var(--text);
  text-anchor: middle; dominant-baseline: central;
}
.nc-label.active { fill: #fff; }

/* Staff / Pentagrama */
.staff-svg { display: block; margin: 0 auto; background: #fafafa; border-radius: 8px; }
.staff-line { stroke: #333; stroke-width: 1; }
.staff-note { fill: #1a1a1a; }
.staff-note.highlight { fill: var(--major); }
.staff-stem { stroke: #1a1a1a; stroke-width: 1.2; }
.staff-label { font-size: 10px; fill: #555; text-anchor: middle; }

/* Interval ladder */
.interval-ladder {
  display: flex; flex-direction: column; gap: 4px;
  font-size: 12px;
}
.interval-row {
  display: grid;
  grid-template-columns: 60px 40px 1fr 80px;
  align-items: center;
  gap: 10px;
  padding: 6px 10px;
  background: rgba(255,255,255,0.02);
  border-radius: 6px;
}
.interval-row .int-name { color: var(--text); font-weight: 500; }
.interval-row .int-st { color: var(--text-muted); font-variant-numeric: tabular-nums; text-align: right; }
.interval-row .int-bar {
  height: 8px; background: rgba(255,255,255,0.05); border-radius: 4px; overflow: hidden;
}
.interval-row .int-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--minor), var(--major));
  border-radius: 4px;
}
.interval-row .int-example { color: var(--text-muted); font-family: monospace; font-size: 11px; text-align: right; }

/* Chord cards / grid */
.chord-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 10px;
  margin: 14px 0;
}
.chord-card {
  background: rgba(255,255,255,0.03);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 10px;
  padding: 12px;
  text-align: center;
}
.chord-card .cc-name {
  font-size: 18px; font-weight: 600; color: #fff;
  margin-bottom: 4px;
}
.chord-card .cc-roman {
  font-size: 11px; color: var(--text-muted);
  margin-bottom: 8px; letter-spacing: 0.5px;
}
.chord-card .cc-notes {
  font-size: 11px; color: var(--minor); font-family: monospace;
}
.chord-card.major { border-color: rgba(232,67,147,0.3); }
.chord-card.major .cc-name { color: var(--major); }
.chord-card.minor { border-color: rgba(0,206,201,0.3); }
.chord-card.minor .cc-name { color: var(--minor); }
.chord-card.dim { border-color: rgba(162,155,254,0.3); }
.chord-card.dim .cc-name { color: var(--dim); }
.chord-card.aug { border-color: rgba(85,239,196,0.3); }
.chord-card.aug .cc-name { color: var(--aug); }

/* Solo visible para lectores de pantalla */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* Roman progression bar */
.prog-bar {
  display: flex; gap: 8px; flex-wrap: wrap;
  padding: 14px;
  background: rgba(20,20,20,0.6);
  border-radius: 8px;
  justify-content: center;
}
.prog-step {
  min-width: 60px;
  padding: 10px 14px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 8px;
  text-align: center;
}
.prog-step .ps-roman {
  font-size: 16px; font-weight: 600; color: #fff;
  margin-bottom: 2px;
}
.prog-step .ps-chord {
  font-size: 11px; color: var(--text-muted);
}
.prog-arrow { color: var(--text-muted); align-self: center; }
.prog-play-all {
  align-self: center;
  padding: 8px 14px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 8px;
  color: #fff;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s;
}
.prog-play-all:hover { background: rgba(255,255,255,0.16); }

/* Fretboard */
.fretboard-svg { display: block; margin: 0 auto; }
.fret-line { stroke: #555; stroke-width: 1; }
.fret-line.nut { stroke: #ccc; stroke-width: 3; }
.string-line { stroke: #888; stroke-width: 1; }
.fret-dot { fill: #333; }
.fret-marker { fill: var(--major); }
.fret-label { font-size: 10px; fill: #fff; text-anchor: middle; dominant-baseline: central; font-weight: 600; }
.fret-num { font-size: 9px; fill: var(--text-muted); text-anchor: middle; }

/* Scale degree table */
.scale-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
  margin: 10px 0;
}
.scale-table th, .scale-table td {
  padding: 8px 10px;
  text-align: center;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.scale-table th {
  color: var(--text-muted);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  font-weight: 500;
}
.scale-table td { color: var(--text); }
.scale-table td.tonic { color: var(--major); font-weight: 600; }
.scale-table td.subdom { color: var(--subdominant); font-weight: 600; }
.scale-table td.dom { color: var(--dominant); font-weight: 600; }

/* Practice / Tip blocks */
.tip-block, .practice-block {
  padding: 14px 16px;
  border-radius: 10px;
  margin: 16px 0;
  font-size: 13px;
  line-height: 1.6;
}
.tip-block {
  background: rgba(0,206,201,0.06);
  border: 1px solid rgba(0,206,201,0.2);
}
.tip-block .block-label {
  color: var(--minor);
  font-weight: 600; font-size: 10px;
  text-transform: uppercase; letter-spacing: 0.8px;
  margin-bottom: 6px;
}
.practice-block {
  background: rgba(253,203,110,0.06);
  border: 1px solid rgba(253,203,110,0.2);
}
.practice-block .block-label {
  color: var(--dom7);
  font-weight: 600; font-size: 10px;
  text-transform: uppercase; letter-spacing: 0.8px;
  margin-bottom: 6px;
}

/* Nav (anclado al fondo del viewport, semi-translúcido) */
#lesson-nav {
  position: sticky;
  bottom: 0;
  grid-row: 2 / 3;
  grid-column: 2 / 3;
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 16px;
  margin: 16px -16px -16px;
  border-top: 1px solid rgba(255,255,255,0.08);
  background: rgba(10,10,10,0.85);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  z-index: 50;
  border-radius: 12px 12px 0 0;
}
.lesson-nav-btn {
  background: rgba(20,20,20,0.85);
  border: 1px solid rgba(255,255,255,0.1);
  color: var(--text);
  padding: 10px 18px;
  border-radius: 10px;
  font-size: 12px;
  font-family: inherit; font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}
.lesson-nav-btn:hover {
  background: rgba(30,30,30,0.95);
  border-color: rgba(255,255,255,0.25);
  color: #fff;
}
.lesson-nav-btn:disabled {
  opacity: 0.3; cursor: not-allowed;
}
.lesson-progress {
  font-size: 11px; color: var(--text-muted);
  letter-spacing: 0.4px;
}

/* Modes grid */
.modes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin: 14px 0;
}
.mode-card {
  background: rgba(255,255,255,0.03);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 10px;
  padding: 14px;
}
.mode-card .mode-name {
  font-size: 14px; color: #fff; font-weight: 600;
  margin-bottom: 2px;
}
.mode-card .mode-flavor {
  font-size: 11px; color: var(--dom7);
  margin-bottom: 8px;
  text-transform: uppercase; letter-spacing: 0.5px;
}
.mode-card .mode-notes {
  font-size: 11px; color: var(--minor);
  font-family: monospace;
  margin-bottom: 8px;
}
.mode-card .mode-desc {
  font-size: 12px; color: var(--text-muted);
  line-height: 1.5;
}

/* Form diagram (secciones de una forma musical) */
.form-diagram {
  display: flex; flex-wrap: wrap; gap: 6px;
  margin: 14px 0;
}
.form-block {
  flex: 1 1 60px;
  min-width: 52px;
  padding: 14px 10px;
  border-radius: 8px;
  text-align: center;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.1);
}
.form-block .fb-label {
  display: block;
  font-size: 18px; font-weight: 700; color: #fff;
  letter-spacing: 0.5px;
}
.form-block .fb-desc {
  display: block;
  font-size: 10px; color: var(--text-muted);
  margin-top: 4px; line-height: 1.3;
}
.form-block.a { background: rgba(232,67,147,0.12); border-color: rgba(232,67,147,0.4); }
.form-block.a .fb-label { color: var(--major); }
.form-block.b { background: rgba(0,206,201,0.12); border-color: rgba(0,206,201,0.4); }
.form-block.b .fb-label { color: var(--minor); }
.form-block.c { background: rgba(253,203,110,0.12); border-color: rgba(253,203,110,0.4); }
.form-block.c .fb-label { color: var(--dom7); }
.form-block.d { background: rgba(162,155,254,0.12); border-color: rgba(162,155,254,0.4); }
.form-block.d .fb-label { color: var(--dim); }
.form-block.intro, .form-block.outro { background: rgba(255,255,255,0.03); }
.form-block.intro .fb-label, .form-block.outro .fb-label { color: var(--text-muted); font-size: 13px; }

/* Info cards (genéricas, sin audio) */
.info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 10px;
  margin: 14px 0;
}
.info-card {
  background: rgba(255,255,255,0.03);
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 10px;
  padding: 13px 14px;
}
.info-card .ic-name { font-size: 14px; font-weight: 600; color: #fff; margin-bottom: 2px; }
.info-card .ic-sub {
  font-size: 10px; color: var(--dom7);
  text-transform: uppercase; letter-spacing: 0.5px;
  margin-bottom: 7px; font-family: monospace;
}
.info-card .ic-desc { font-size: 12px; color: var(--text-muted); line-height: 1.5; }
.info-card.strings { border-color: rgba(232,67,147,0.3); }
.info-card.winds { border-color: rgba(0,206,201,0.3); }
.info-card.brass { border-color: rgba(253,203,110,0.3); }
.info-card.perc { border-color: rgba(162,155,254,0.3); }

/* Range chart (tesituras de instrumentos) */
.range-chart {
  display: flex; flex-direction: column; gap: 5px;
  margin: 14px 0;
  font-size: 12px;
}
.rc-head, .rc-row {
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr);
  align-items: center;
  gap: 10px;
}
.rc-name { color: var(--text); font-size: 11px; text-align: right; }
.rc-trackhead { position: relative; height: 14px; }
.rc-grid {
  position: absolute; top: 0;
  transform: translateX(-50%);
  font-size: 9px; color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}
.rc-grid::after {
  content: ''; position: absolute; left: 50%; top: 14px;
  width: 1px; height: 1000px;
  background: rgba(255,255,255,0.04);
  transform: translateX(-50%);
  pointer-events: none;
}
.rc-track {
  position: relative; height: 13px;
  background: rgba(255,255,255,0.04);
  border-radius: 7px;
}
.rc-bar {
  position: absolute; top: 0; bottom: 0;
  border-radius: 7px;
  background: linear-gradient(90deg, var(--minor), var(--major));
}
.rc-bar.strings { background: linear-gradient(90deg, rgba(232,67,147,0.6), var(--major)); }
.rc-bar.winds   { background: linear-gradient(90deg, rgba(0,206,201,0.6), var(--minor)); }
.rc-bar.brass   { background: linear-gradient(90deg, rgba(253,203,110,0.6), var(--dom7)); }
.rc-bar.perc    { background: linear-gradient(90deg, rgba(162,155,254,0.6), var(--dim)); }
.rc-bar.voz     { background: linear-gradient(90deg, rgba(85,239,196,0.6), var(--aug)); }

/* ============================================================
   RESPONSIVE
   ============================================================ */

/* Tablet & abajo: oculta sidebar, una sola columna */
/* ============================================================
   PROGRESO: checks de lecciones visitadas + contador por nivel
   ============================================================ */
.lesson-check {
  display: inline-block;
  margin-left: 5px;
  color: rgba(255, 255, 255, 0.35); /* visitada: check tenue */
  font-size: 0.85em;
  font-weight: 600;
}
.lesson-check.completed {
  color: rgba(85, 239, 196, 0.95); /* completada (quiz perfecto): check verde */
  text-shadow: 0 0 6px rgba(85, 239, 196, 0.35);
}
#sidebar-list li .lesson-check { margin-left: 4px; }
.chip-progress {
  display: inline-block;
  margin-left: 5px;
  font-size: 9px;
  color: rgba(255,255,255,0.35);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.3px;
}
.chip.active .chip-progress { color: rgba(255,255,255,0.55); }

/* ============================================================
   BANNER "CONTINUAR DONDE QUEDASTE"
   ============================================================ */
.resume-banner {
  display: flex;
  align-items: center;
  gap: 6px;
  max-width: 1232px;
  width: calc(100% - 48px);
  margin: 16px auto -8px;
  background: rgba(232,67,147,0.06);
  border: 1px solid rgba(232,67,147,0.25);
  border-radius: 10px;
  padding: 2px 4px;
}
.resume-banner.hidden { display: none; }
.resume-banner-link {
  flex: 1;
  min-width: 0;
  text-align: left;
  background: none;
  border: none;
  color: var(--major);
  font-family: inherit;
  font-size: 12px;
  line-height: 1.5;
  padding: 8px 10px;
  cursor: pointer;
  border-radius: 8px;
  transition: background 0.15s, color 0.15s;
}
.resume-banner-link:hover { background: rgba(232,67,147,0.08); color: #fff; }
.resume-banner-dismiss {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 12px;
  font-family: inherit;
  cursor: pointer;
  padding: 6px 10px;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}
.resume-banner-dismiss:hover { color: #fff; background: rgba(255,255,255,0.08); }

/* ============================================================
   BUSCADOR DE LECCIONES (header)
   ============================================================ */
#lesson-search {
  position: relative;
  display: flex;
  align-items: center;
  gap: 4px;
}
#search-toggle { min-width: 28px; }
#search-input {
  width: 0;
  padding: 5px 0;
  opacity: 0;
  border: 1px solid transparent;
  background: rgba(20,20,20,0.85);
  border-radius: 8px;
  color: var(--text);
  font-family: inherit;
  font-size: 11px;
  outline: none;
  transition: width 0.2s ease, opacity 0.2s ease, padding 0.2s ease;
}
#lesson-search.open #search-input {
  width: 170px;
  padding: 5px 10px;
  opacity: 1;
  border-color: rgba(255,255,255,0.15);
}
#search-input:focus { border-color: var(--major); }
#search-input::placeholder { color: var(--text-muted); }
.search-dropdown {
  position: absolute;
  top: 100%;
  right: 0;
  margin-top: 4px;
  background: rgba(20,20,20,0.97);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 10px;
  padding: 4px;
  backdrop-filter: blur(12px);
  z-index: 220;
  width: max-content;
  min-width: 260px;
  max-width: min(340px, calc(100vw - 24px));
  max-height: 320px;
  overflow-y: auto;
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}
.search-dropdown.hidden { display: none; }
.search-result {
  display: flex;
  width: 100%;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 7px 10px;
  font-size: 12px;
  font-family: inherit;
  cursor: pointer;
  border-radius: 6px;
  text-align: left;
  transition: background 0.15s, color 0.15s;
}
.search-result:hover,
.search-result.active { background: rgba(255,255,255,0.08); color: var(--text); }
.search-result .sr-title { flex: 1; min-width: 0; line-height: 1.35; }
.search-result .sr-title mark {
  background: none;
  color: var(--major);
  font-weight: 600;
}
.search-result .sr-level {
  font-size: 9px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: rgba(255,255,255,0.3);
  white-space: nowrap;
}
.search-empty {
  padding: 8px 10px;
  font-size: 11px;
  color: var(--text-muted);
  font-style: italic;
}

/* Hint de navegación por teclado en la barra de lecciones */
.lesson-progress-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}
.kbd-hint {
  font-size: 9px;
  color: rgba(255,255,255,0.22);
  letter-spacing: 2px;
  line-height: 1;
  user-select: none;
}

@media (max-width: 900px) {
  #learn-main {
    grid-template-columns: 1fr;
    padding: 18px;
    gap: 16px;
  }
  #lesson-sidebar {
    position: relative;
    top: auto;
    max-height: none;
    display: none;
  }
  #lesson-content { grid-column: 1 / 2; max-width: 100%; }
  #lesson-nav { grid-column: 1 / 2; }
  #lesson-content h2 { font-size: 22px; }
}

/* Mobile: header reorganizado, elementos más holgados */
@media (max-width: 640px) {
  #learn-header {
    padding: 10px 12px 8px;
    gap: 10px;
  }
  #header-top {
    flex-wrap: wrap;
    gap: 8px;
  }
  .header-left {
    gap: 8px;
    flex: 1;
    min-width: 0;
  }
  #learn-header h1 {
    font-size: 13px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .title-section { font-size: 12px; }
  .header-actions {
    gap: 4px;
    flex-shrink: 0;
  }
  .header-actions .tr-toggle {
    font-size: 10px;
    padding: 4px 8px;
  }
  .back-link {
    min-width: 28px;
    padding: 4px 8px;
    font-size: 13px;
  }
  /* Texto de los toggles más corto en mobile */
  #auto-play-toggle { font-size: 0; padding: 5px 8px; min-width: 28px; }
  #auto-play-toggle::before {
    content: '🔇';
    font-size: 13px;
  }
  body.autoplay-on #auto-play-toggle::before { content: '🔊'; }
  #instrument-toggle { font-size: 0; padding: 5px 8px; min-width: 28px; }
  #instrument-toggle::before {
    content: '🎹';
    font-size: 13px;
  }
  #instrument-toggle.active::before { content: '🎸'; }

  /* Chip rows en mobile */
  .chip-row { padding-bottom: 0; }
  .chip-label { display: none; }
  #level-chips { gap: 4px; overflow-x: auto; }
  #level-chips .chip { flex-shrink: 0; }
  .chip { padding: 5px 10px; font-size: 11px; }

  /* Main: padding más reducido pero respiración vertical */
  #learn-main {
    padding: 14px 12px 24px;
    gap: 10px;
  }
  #lesson-content { padding: 4px 0 28px; }

  /* Tipografía contenido */
  #lesson-content .lesson-eyebrow { font-size: 9px; }
  #lesson-content h2 { font-size: 20px; line-height: 1.25; margin-bottom: 6px; }
  #lesson-content .lesson-summary { font-size: 13px; margin-bottom: 20px; }
  #lesson-content h3 { font-size: 15px; margin-top: 24px; }
  #lesson-content h4 { font-size: 12px; }
  #lesson-content p, #lesson-content ul, #lesson-content ol { font-size: 13px; line-height: 1.65; }

  /* Visual blocks */
  .visual { padding: 12px; margin: 14px -4px; border-radius: 10px; }

  /* Selector tonalidad: stack vertical */
  .key-selector {
    flex-wrap: wrap;
    padding: 10px 12px;
    gap: 8px;
  }
  .key-selector label { width: 100%; }
  .key-select { flex: 1; min-width: 140px; }
  .key-selector-hint {
    width: 100%;
    margin-left: 0;
    text-align: left;
    font-size: 10px;
  }

  /* Piano: scroll horizontal si excede */
  .piano-wrap {
    overflow-x: auto;
    margin: 0 -10px;
    padding: 0 10px;
    -webkit-overflow-scrolling: touch;
  }
  .piano-wrap::-webkit-scrollbar { height: 4px; }
  .piano-wrap::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.15); border-radius: 2px; }

  /* Note circle: encogerlo */
  .note-circle-svg { max-width: 100%; height: auto; }

  /* Pentagrama */
  .staff-svg { max-width: 100%; height: auto; }

  /* Fretboard: scroll horizontal */
  .fretboard-svg {
    max-width: none;
    display: block;
  }
  .visual:has(.fretboard-svg),
  .visual.visual-scroll {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  /* Chord cards: 2 columnas en mobile */
  .chord-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
  }
  .chord-card { padding: 10px 8px; }
  .chord-card .cc-name { font-size: 16px; }
  .chord-card .cc-notes { font-size: 10px; }

  /* Modes grid: 1 columna */
  .modes-grid {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  /* Info grid: 1 columna en mobile */
  .info-grid { grid-template-columns: 1fr; gap: 8px; }

  /* Form diagram: permitir scroll si hay muchas secciones */
  .form-diagram { gap: 4px; }
  .form-block { padding: 10px 6px; min-width: 44px; }
  .form-block .fb-label { font-size: 15px; }
  .form-block .fb-desc { font-size: 9px; }

  /* Range chart: nombre más angosto */
  .rc-head, .rc-row { grid-template-columns: 78px minmax(0, 1fr); gap: 8px; }
  .rc-name { font-size: 10px; }

  /* Progresiones */
  .prog-bar {
    padding: 12px 8px;
    gap: 6px;
  }
  .prog-step {
    min-width: 50px;
    padding: 8px 10px;
  }
  .prog-step .ps-roman { font-size: 14px; }
  .prog-step .ps-chord { font-size: 10px; }
  .prog-arrow { font-size: 12px; }
  .prog-play-all {
    width: 100%;
    margin-top: 6px;
  }

  /* Intervalos: más compacto */
  .interval-row {
    grid-template-columns: 70px 30px 1fr 60px;
    gap: 8px;
    padding: 6px 8px;
    font-size: 11px;
  }
  .interval-row .int-example { font-size: 10px; }

  /* Tablas: scroll horizontal */
  #lesson-content table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    white-space: nowrap;
  }
  .scale-table { font-size: 11px; }
  .scale-table th, .scale-table td { padding: 6px 8px; }

  /* Tip y practice más compactos */
  .tip-block, .practice-block {
    padding: 12px 14px;
    font-size: 12px;
  }

  /* Navegación de lecciones (sticky al fondo en mobile también) */
  #lesson-nav {
    margin: 12px -12px -14px;
    padding: 10px 12px;
    gap: 8px;
  }
  .lesson-nav-btn {
    padding: 8px 12px;
    font-size: 11px;
  }
  .lesson-progress { font-size: 10px; }
  /* Padding extra al final del contenido para que la nav no tape la última línea */
  #lesson-content { padding-bottom: 80px; }

  /* Banner idioma */
  .lang-banner { font-size: 11px; padding: 8px 12px; }

  /* Lang dropdown alineado al borde derecho del contenedor */
  .lang-dropdown { right: 0; min-width: 110px; }

  /* Banner "continuar" */
  .resume-banner { width: calc(100% - 24px); margin-top: 12px; }
  .resume-banner-link { font-size: 11px; padding: 7px 8px; }

  /* Buscador: input más angosto, dropdown pegado al borde derecho */
  #lesson-search.open #search-input { width: 120px; }
  .search-dropdown { min-width: 220px; }

  /* Hint de teclado: sin sentido en táctil */
  .kbd-hint { display: none; }
}

/* Mobile pequeño: aún más compacto */
@media (max-width: 380px) {
  #learn-header h1 { font-size: 12px; }
  .title-sep { display: none; }
  .site-title-link { display: none; }
  .header-actions .tr-toggle { padding: 4px 6px; }
  .chip { padding: 4px 8px; font-size: 10px; }
  .chord-grid { grid-template-columns: 1fr; }
  #lesson-content h2 { font-size: 18px; }
}

/* ============================================================
   QUIZ AUTO-CORREGIDO (motor en js/learn-quiz.js)
   Estética alineada con .practice-block / .tip-block
   ============================================================ */
.quiz-block {
  padding: 16px;
  border-radius: 10px;
  margin: 24px 0 8px;
  font-size: 13px;
  line-height: 1.6;
  background: rgba(162, 155, 254, 0.06);
  border: 1px solid rgba(162, 155, 254, 0.25);
}
.quiz-block .block-label {
  color: var(--dim);
  font-weight: 600; font-size: 10px;
  text-transform: uppercase; letter-spacing: 0.8px;
  margin-bottom: 6px;
  display: flex; align-items: baseline; justify-content: space-between; gap: 10px;
}
.quiz-best {
  color: var(--text-muted);
  font-weight: 500;
  text-transform: none;
  letter-spacing: normal;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}
.quiz-q { margin: 14px 0 0; }
.quiz-q-text {
  color: var(--text);
  margin-bottom: 8px;
  display: flex; align-items: center; flex-wrap: wrap; gap: 6px;
}
.quiz-q-num { color: var(--dim); font-weight: 600; }
.quiz-play {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.18);
  color: var(--text);
  border-radius: 8px;
  padding: 3px 12px;
  font-family: inherit; font-size: 12px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
}
.quiz-play:hover { border-color: var(--major); color: #fff; }
.quiz-options {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 8px;
}
.quiz-option {
  background: rgba(20,20,20,0.85);
  border: 1px solid rgba(255,255,255,0.12);
  color: var(--text);
  border-radius: 8px;
  padding: 8px 10px;
  font-family: inherit; font-size: 12px; font-weight: 500;
  cursor: pointer;
  text-align: center;
  transition: border-color 0.15s, background 0.15s, color 0.15s;
}
.quiz-option:hover:not(:disabled) { border-color: rgba(255,255,255,0.4); }
.quiz-option:disabled { cursor: default; }
.quiz-option.correct {
  border-color: var(--aug);
  background: rgba(85,239,196,0.12);
  color: var(--aug);
}
.quiz-option.wrong {
  border-color: #e17055;
  background: rgba(225,112,85,0.12);
  color: #e17055;
}
.quiz-feedback { margin-top: 6px; font-size: 12px; min-height: 1.2em; }
.quiz-feedback.ok { color: var(--aug); }
.quiz-feedback.ko { color: #e17055; }
.quiz-result {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid rgba(255,255,255,0.1);
  display: flex; align-items: center; flex-wrap: wrap; gap: 12px;
}
.quiz-result.hidden { display: none; }
.quiz-score { font-weight: 600; color: var(--text); }
.quiz-perfect { color: var(--dom7); font-weight: 600; }
.quiz-retry {
  background: rgba(20,20,20,0.85);
  border: 1px solid rgba(255,255,255,0.15);
  color: var(--text);
  padding: 6px 14px;
  border-radius: 8px;
  font-family: inherit; font-size: 12px; font-weight: 500;
  cursor: pointer;
  transition: border-color 0.15s;
  margin-left: auto;
}
.quiz-retry:hover { border-color: var(--major); }

/* Móvil: chips de opciones en 2 columnas */
@media (max-width: 600px) {
  .quiz-block { padding: 12px; }
  .quiz-options { grid-template-columns: repeat(2, 1fr); }
}