/* =========================================================
   Drum Town — Global Stylesheet
   Aesthetic: ECM-jazz manuscript. Cream + ink + rust.
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,400;0,500;0,600;1,400;1,500&family=Lora:wght@400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg:        #f4ebd9;
  --paper:     #faf3e3;
  --paper-2:   #ede2c8;
  --ink:       #1d1814;
  --ink-2:     #2d251c;
  --ink-3:     #4a4138;
  --ink-soft:  #6b5d4d;
  --rule:      #c9b893;
  --rule-soft: #d8cdb8;
  --accent:    #8b3a2c;     /* rust */
  --accent-2:  #a0432f;
  --ochre:     #b8943f;
  --gold:      #d4a854;
  --shadow:    rgba(29, 24, 20, 0.08);

  --display: 'Cormorant Garamond', Georgia, serif;
  --body:    'Lora', Georgia, serif;
  --mono:    'JetBrains Mono', 'Courier New', monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; }

.container {
  max-width: 920px;
  margin: 0 auto;
  padding: 56px 36px;
}

.container--wide { max-width: 1200px; }

/* =====================  HEADER / NAV  ===================== */
.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--bg);
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-header__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 18px 36px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.site-logo {
  font-family: var(--display);
  font-size: 22px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.01em;
  text-decoration: none;
}

.site-logo em { color: var(--accent); font-style: italic; }

.site-nav {
  margin-left: auto;
  display: flex;
  gap: 22px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.site-nav a {
  color: var(--ink-soft);
  text-decoration: none;
}

.site-nav a:hover, .site-nav a.active { color: var(--accent); }

/* =====================  TYPE / HEADINGS  ===================== */
.tag {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  display: inline-block;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 500;
  margin: 0 0 6px;
}

h1, h2, h3, h4 { font-family: var(--display); font-weight: 500; letter-spacing: -0.01em; }
h1 { font-size: 60px; line-height: 1; margin: 0 0 20px; }
h1 em { font-style: italic; color: var(--accent); font-weight: 400; }
h2 { font-size: 36px; line-height: 1.1; margin: 36px 0 14px; }
h3 { font-size: 24px; line-height: 1.2; margin: 24px 0 10px; }
h4 { font-size: 18px; line-height: 1.3; margin: 18px 0 6px; font-weight: 600; }

p { margin: 0 0 14px; }

.lede {
  font-size: 17px;
  color: var(--ink-3);
  max-width: 600px;
  margin: 0 0 18px;
}

ul.bulleted { padding-left: 20px; margin: 12px 0; font-size: 15.5px; }
ul.bulleted li { margin-bottom: 8px; }

hr.section-rule {
  border: none;
  border-top: 1px solid var(--rule-soft);
  margin: 40px 0;
}

/* =====================  HOMEPAGE — CURRICULUM  ===================== */
.curriculum-hero {
  text-align: center;
  padding: 40px 0 30px;
}
.curriculum-hero h1 { font-size: 80px; }
.curriculum-hero .lede { margin: 0 auto 18px; }
.curriculum-hero .stat {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-soft);
  text-transform: uppercase;
}

.curriculum-section {
  margin-bottom: 72px;
}
.curriculum-section__header {
  text-align: center;
  margin-bottom: 32px;
}
.curriculum-section__header--left {
  text-align: left;
}
.curriculum-section__header--left .lede { margin-left: 0; margin-right: 0; }
.curriculum-section__header h2 {
  font-size: 44px;
  margin: 6px 0 8px;
}
.curriculum-section__header h2 em {
  font-style: italic;
  color: var(--accent);
}
.curriculum-section__header .lede {
  margin: 0 auto;
}

/* Chapters: editorial table-of-contents block used by foundations sub-sections
   and the final mastery section. Title + chapter number on the same row, then
   a tagline, then an inline flowing numbered list of lessons. */
.chapter {
  margin: 40px 0;
  padding-top: 14px;
  border-top: 1px solid var(--rule-soft);
}
.chapter__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
}
.chapter__title {
  font-family: var(--display);
  font-size: 36px;
  font-weight: 500;
  font-style: italic;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--ink);
}
.chapter__num {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  white-space: nowrap;
}
.chapter__lessons {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  row-gap: 10px;
}
.chapter__lessons > li {
  display: inline-flex;
  align-items: baseline;
}
.chapter__lessons > li::after {
  content: '';
  display: inline-block;
  width: 22px;
  border-top: 1px solid var(--rule);
  margin: 0 12px;
  transform: translateY(-4px);
}
.chapter__lessons > li:last-child::after { display: none; }

.chapter-lesson {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  text-decoration: none;
  color: var(--ink);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 6px 14px;
}
.chapter-lesson:hover { border-color: var(--accent); }
.chapter-lesson__num {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  color: var(--ink-soft);
}
.chapter-lesson__title {
  font-family: var(--display);
  font-size: 17px;
  font-style: italic;
}
.chapter-lesson:hover { text-decoration: none; }
.chapter-lesson:hover .chapter-lesson__title { color: var(--accent); }

.chapter-lesson.is-visited { border-color: var(--ochre); }
.chapter-lesson.is-visited .chapter-lesson__num { color: var(--ochre); }
.chapter-lesson.is-visited .chapter-lesson__title { color: var(--ochre); }

.chapter-lesson.is-last-visited { border-color: var(--accent); background: var(--accent); }
.chapter-lesson.is-last-visited .chapter-lesson__num,
.chapter-lesson.is-last-visited .chapter-lesson__title { color: var(--paper); }
.chapter-lesson.is-last-visited:hover .chapter-lesson__title { color: var(--paper); }

/* Mastery: horizontal rail of cross-cutting topics */
/* Hero — "Up Next" state: shown when localStorage holds a lastVisited slug
   that maps to a known lesson with a next neighbor. Replaces the default
   curriculum-hero on the homepage. */
.hero-default__completed {
  font-family: var(--body);
  font-size: 14.5px;
  color: var(--ink-soft);
  margin-top: 18px;
}
.hero-default__completed a { color: var(--accent); }

.hero-upnext {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  gap: 48px;
  align-items: start;
  padding: 32px 0 40px;
  border-bottom: 1px solid var(--rule);
  margin-bottom: 48px;
}
.hero-upnext[hidden] { display: none; }
@media (max-width: 880px) {
  .hero-upnext { grid-template-columns: 1fr; gap: 28px; }
}
.hero-upnext--no-preview { grid-template-columns: 1fr; }
.hero-upnext__main { min-width: 0; }
.hero-upnext__eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 18px;
}
.hero-upnext__eyebrow-lead { font-weight: 500; }
.hero-upnext__dot { margin: 0 8px; color: var(--accent); }
.hero-upnext__title {
  font-family: var(--display);
  font-style: italic;
  font-size: 72px;
  line-height: 1;
  margin: 0 0 18px;
  color: var(--accent);
  font-weight: 500;
}
.hero-upnext__tagline {
  font-family: var(--body);
  font-size: 17px;
  color: var(--ink-3);
  max-width: 540px;
  margin: 0 0 24px;
}
.hero-upnext__actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 11px 20px;
  font-family: var(--display);
  font-size: 16px;
  font-style: italic;
  letter-spacing: 0.01em;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.btn:hover { text-decoration: none; }
.btn--primary {
  background: var(--accent);
  color: var(--paper);
  border-color: var(--accent);
}
.btn--primary:hover {
  background: var(--accent-2);
  border-color: var(--accent-2);
  color: var(--paper);
}
.btn--ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--rule);
}
.btn--ghost:hover { border-color: var(--ink-soft); color: var(--ink); }

/* Preview card on the right side of the Up Next hero. */
.preview-card {
  background: var(--paper);
  border: 1px solid var(--rule);
  padding: 20px 22px 18px;
}
.preview-card__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 8px;
}
.preview-card__notation {
  margin: 6px -8px 4px;
  min-height: 90px;
  overflow: hidden;
}
.preview-card__notation svg {
  max-width: 100%;
  height: auto;
  display: block;
}
.preview-card__caption {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-top: 2px;
}
.preview-card__rule {
  border: none;
  border-top: 1px dashed var(--rule);
  margin: 16px 0 14px;
}
.preview-card__rel {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}
.preview-card__rel-label {
  display: block;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 4px;
}
.preview-card__rel-title {
  font-family: var(--display);
  font-style: italic;
  font-size: 17px;
  color: var(--ink);
}

/* =====================  GENRE OVERVIEW  ===================== */
.genre-hero {
  border-bottom: 1px solid var(--rule);
  padding-bottom: 32px;
  margin-bottom: 40px;
}
.genre-hero h1 { font-size: 64px; }

.level-block {
  margin-bottom: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--rule-soft);
}
.level-block:first-of-type { border: none; padding-top: 0; }

.level-block__header {
  display: flex;
  align-items: baseline;
  gap: 20px;
  margin-bottom: 18px;
}
.level-block__num {
  font-family: var(--display);
  font-size: 44px;
  font-style: italic;
  color: var(--accent);
  font-weight: 500;
  line-height: 1;
}
.level-block__title {
  font-family: var(--display);
  font-size: 30px;
  margin: 0;
  font-weight: 500;
}
.level-block__tag {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-left: auto;
}

.lesson-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.lesson-row a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  background: var(--paper);
  border: 1px solid var(--rule);
  text-decoration: none;
  color: var(--ink);
  transition: transform 0.1s ease, border-color 0.15s ease;
}
.lesson-row a:hover {
  transform: translateX(2px);
  border-color: var(--accent);
  text-decoration: none;
}
.lesson-row__title {
  font-family: var(--display);
  font-size: 19px;
}
.lesson-row__status {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.lesson-row a.is-ready .lesson-row__status { color: var(--accent); }

/* =====================  LESSON LAYOUT + SIDEBAR  ===================== */
.lesson-layout {
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
  align-items: start;
}

.curriculum-sidebar {
  position: sticky;
  top: 60px;            /* sit below the sticky site-header */
  height: calc(100vh - 60px);
  overflow-y: auto;
  border-right: 1px solid var(--rule);
  background: var(--paper);
  padding: 22px 14px 40px 22px;
}
.curriculum-sidebar::-webkit-scrollbar { width: 6px; }
.curriculum-sidebar::-webkit-scrollbar-track { background: transparent; }
.curriculum-sidebar::-webkit-scrollbar-thumb {
  background: var(--rule);
  border-radius: 3px;
}
.curriculum-sidebar::-webkit-scrollbar-thumb:hover { background: var(--ink-soft); }

.island-header {
  padding-bottom: 14px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--rule-soft);
}
.island-back {
  display: inline-block;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
  text-decoration: none;
  margin-bottom: 8px;
}
.island-back:hover { color: var(--accent); text-decoration: none; }
.island-title { display: flex; flex-direction: column; gap: 2px; }
.island-eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
}
.island-name {
  font-family: var(--display);
  font-size: 26px;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.01em;
  line-height: 1.05;
}
.island-tagline {
  font-family: var(--display);
  font-style: italic;
  color: var(--ink-soft);
  font-size: 14px;
  margin: -6px 0 14px;
}

.curr-section { margin-bottom: 14px; }
.curr-section:last-child { margin-bottom: 0; }

.curr-section__title {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 5px;
  font-weight: 500;
}

.curr-list { list-style: none; margin: 0; padding: 0; }
.curr-item { margin: 0; }

.curr-item a {
  display: block;
  padding: 4px 10px 4px 12px;
  font-family: var(--display);
  font-size: 14.5px;
  line-height: 1.3;
  color: var(--ink-3);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color 0.12s ease, background 0.12s ease, border-color 0.12s ease;
}
.curr-item a:hover {
  color: var(--accent);
  background: var(--paper-2);
  text-decoration: none;
}
.curr-item.is-stub a { color: var(--ink-soft); }
.curr-item.is-current a {
  background: var(--paper-2);
  color: var(--ink);
  border-left-color: var(--accent);
  font-weight: 500;
}

/* =====================  LESSON PAGE  ===================== */
.lesson-hero {
  border-bottom: 1px solid var(--rule);
  padding-bottom: 28px;
  margin-bottom: 36px;
}
.lesson-hero h1 { font-size: 52px; margin-bottom: 12px; }
.lesson-hero .breadcrumb {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 12px;
}
.lesson-hero .breadcrumb a { color: var(--ink-soft); }
.lesson-hero .breadcrumb a:hover { color: var(--accent); }

.lesson-meta {
  display: flex;
  gap: 24px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
  flex-wrap: wrap;
}
.lesson-meta strong { color: var(--accent); font-weight: 500; }

.section-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 28px 0 8px;
  font-weight: 500;
}

.lesson-prose {
  font-size: 16px;
  color: var(--ink-2);
}
.lesson-prose p { margin: 0 0 14px; }
.lesson-prose strong { color: var(--ink); font-weight: 600; }
.lesson-prose em { color: var(--ink-soft); }

/* =====================  EXERCISE BLOCK  ===================== */
.exercise {
  background: var(--paper);
  border: 1px solid var(--rule);
  padding: 22px 24px;
  margin: 16px 0 22px;
}

.exercise-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 14px;
}

.exercise-header__text { min-width: 0; }

.exercise-title {
  font-family: var(--display);
  font-size: 22px;
  font-weight: 500;
  margin: 0 0 4px;
}

.exercise-meta {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.06em;
  color: var(--accent);
}

.exercise-controls {
  display: inline-flex;
  align-items: stretch;
  gap: 8px;
  flex-shrink: 0;
}

.kit-selector__select {
  appearance: none;
  -webkit-appearance: none;
  background: transparent;
  border: 1px solid var(--rule);
  color: var(--ink);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  padding: 0 26px 0 10px;
  cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--ink-soft) 50%),
                    linear-gradient(135deg, var(--ink-soft) 50%, transparent 50%);
  background-position: calc(100% - 13px) 50%, calc(100% - 9px) 50%;
  background-size: 4px 4px, 4px 4px;
  background-repeat: no-repeat;
}
.kit-selector__select:hover { border-color: var(--accent); color: var(--accent); }
.kit-selector__select:focus { outline: none; border-color: var(--accent); }

.play-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--ink);
  color: var(--bg);
  border: none;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  padding: 9px 14px 9px 12px;
  cursor: pointer;
  flex-shrink: 0;
  transition: background 0.12s ease, transform 0.08s ease;
}
.play-btn:hover { background: var(--accent); }
.play-btn:active { transform: translateY(1px); }
.play-btn:disabled { cursor: default; opacity: 0.85; }
.play-btn.is-loading { background: var(--ink-soft); cursor: wait; }
.play-btn.is-loading .play-btn__icon { animation: play-pulse 0.5s ease-in-out infinite; }
.play-btn.is-playing { background: var(--accent); }
.play-btn__icon { font-size: 13px; line-height: 1; color: var(--gold); }
.play-btn__label { line-height: 1; }

@keyframes play-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.45; }
}

.notation {
  background: white;
  border: 1px solid var(--rule-soft);
  padding: 6px;
  overflow-x: auto;
  margin: 10px 0;
}

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

.notation svg .playhead {
  stroke: var(--accent);
  stroke-width: 1.8;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.12s ease;
}
.notation svg .playhead.is-active { opacity: 0.55; }

.notation-error {
  padding: 18px;
  color: var(--accent);
  font-style: italic;
  font-size: 14px;
}

.exercise-tip {
  font-style: italic;
  color: var(--ink-3);
  font-size: 14px;
  margin-top: 10px;
  padding-left: 14px;
  border-left: 2px solid var(--ochre);
}
.exercise-tip em { font-style: normal; color: var(--ink); font-weight: 500; }

/* =====================  TIPS / CALLOUTS  ===================== */
.tips, .callout {
  background: var(--paper-2);
  padding: 14px 18px;
  border-left: 3px solid var(--accent);
  margin: 14px 0;
  font-size: 14.5px;
  color: var(--ink-2);
}
.tips strong, .callout strong { color: var(--accent); font-weight: 600; }

/* =====================  PREREQUISITES  ===================== */
.prereqs {
  background: var(--paper);
  border: 1px solid var(--rule);
  padding: 14px 18px;
  margin: 18px 0 28px;
  font-size: 14px;
}
.prereqs__label {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
  display: block;
}
.prereqs ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.prereqs li a {
  background: var(--paper-2);
  padding: 4px 10px;
  font-size: 13px;
  border: 1px solid var(--rule);
  display: inline-block;
}
.prereqs li a:hover { background: var(--accent); color: var(--paper); border-color: var(--accent); text-decoration: none; }

/* =====================  GRADUATION CRITERIA  ===================== */
.grad-criteria {
  background: var(--paper);
  border: 1px solid var(--rule);
  padding: 14px 18px 16px;
  margin: 32px 0 0;
  font-size: 14.5px;
}
.grad-criteria__label {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 8px;
  display: block;
}
.grad-criteria ul { list-style: none; margin: 0; padding: 0; }
.grad-criteria li {
  padding: 4px 0 4px 22px;
  position: relative;
  color: var(--ink-2);
  line-height: 1.5;
}
.grad-criteria li::before {
  content: '✓';
  position: absolute;
  left: 0;
  top: 4px;
  color: var(--accent);
  font-weight: 600;
}

/* =====================  STUB / COMING SOON  ===================== */
.stub-message {
  background: var(--paper);
  border: 1px dashed var(--ochre);
  padding: 32px;
  text-align: center;
  margin: 40px 0;
}
.stub-message h3 { color: var(--accent); margin: 0 0 8px; }

/* =====================  LISTENING / FOOTER  ===================== */
.listening {
  margin: 48px 0 0;
}
.listening__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule-soft);
  margin-bottom: 16px;
}
.listening__eyebrow { color: var(--accent); font-weight: 500; }
.listening__count { color: var(--ink-soft); }
.listening__title {
  font-family: var(--display);
  font-style: italic;
  font-size: 32px;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 0 0 6px;
}
.listening__intro {
  font-family: var(--display);
  font-style: italic;
  font-size: 16px;
  color: var(--ink-soft);
  margin: 0 0 22px;
  max-width: 640px;
}
.listening__list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.listening__item {
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: 14px;
  padding: 14px 0;
  border-top: 1px solid var(--rule-soft);
}
.listening__item:last-child { border-bottom: 1px solid var(--rule-soft); }
.listening__num {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--ink-soft);
  padding-top: 5px;
}
.listening__body { min-width: 0; }
.listening__head-line {
  margin: 0 0 4px;
  color: var(--ink);
  font-size: 16px;
  line-height: 1.4;
}
.listening__artist {
  color: var(--accent);
  font-family: var(--display);
  font-size: 18px;
  font-weight: 500;
}
.listening__dot { margin: 0 6px; color: var(--ink-soft); }
.listening__work {
  font-family: var(--display);
  font-style: italic;
  font-size: 18px;
}
.listening__context {
  margin-left: 10px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.listening__note {
  margin: 0;
  font-size: 14.5px;
  color: var(--ink-3);
  line-height: 1.55;
}

.site-footer {
  margin-top: 80px;
  padding: 32px 36px;
  border-top: 1px solid var(--rule);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--ink-soft);
  text-align: center;
}

/* =====================  METRONOME (persistent)  ===================== */
.metronome {
  position: fixed;
  bottom: 18px;
  right: 18px;
  z-index: 50;
  width: 168px;
  background: var(--paper);
  border: 1px solid var(--rule);
  border-radius: 8px;
  box-shadow: 0 6px 22px var(--shadow);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-family: var(--mono);
}

.metronome__beats {
  display: flex;
  gap: 8px;
  justify-content: center;
  align-items: center;
  min-height: 10px;
}
.metronome__beat {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--rule);
  transition: background 60ms ease, transform 60ms ease;
}
.metronome__beat.is-active {
  background: var(--accent);
  transform: scale(1.5);
}
.metronome__beat.is-downbeat-active {
  background: var(--gold);
  transform: scale(1.7);
}

.metronome__row {
  display: flex;
  align-items: center;
  gap: 6px;
}
.metronome__row--vol { gap: 8px; }

.metronome__btn {
  background: var(--ink);
  color: var(--bg);
  border: none;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  transition: background 0.12s ease;
  flex-shrink: 0;
}
.metronome__btn:hover { background: var(--accent); }
.metronome__btn.is-playing { background: var(--accent); }
.metronome__icon {
  font-size: 11px;
  line-height: 1;
  color: var(--gold);
}

.metronome__bpm {
  flex: 1;
  min-width: 0;
  background: transparent;
  border: 1px solid var(--rule);
  border-radius: 3px;
  font-family: var(--mono);
  font-size: 12px;
  padding: 4px 4px;
  text-align: center;
  color: var(--ink);
  -moz-appearance: textfield;
}
.metronome__bpm::-webkit-outer-spin-button,
.metronome__bpm::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.metronome__bpm:focus { outline: none; border-color: var(--accent); }

/* Range inputs (tempo slider, volume slider) — shared style */
.metronome__slider,
.metronome__volume {
  -webkit-appearance: none;
  appearance: none;
  height: 4px;
  background: var(--rule);
  border-radius: 2px;
  outline: none;
  margin: 0;
  cursor: pointer;
  flex: 1;
  min-width: 0;
}
.metronome__slider { width: 100%; }
.metronome__slider::-webkit-slider-thumb,
.metronome__volume::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
}
.metronome__slider::-moz-range-thumb,
.metronome__volume::-moz-range-thumb {
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
}

.metronome__timesig {
  background: transparent;
  border: 1px solid var(--rule);
  border-radius: 3px;
  font-family: var(--mono);
  font-size: 11px;
  padding: 4px 16px 4px 6px;
  color: var(--ink);
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--ink-soft) 50%),
                    linear-gradient(135deg, var(--ink-soft) 50%, transparent 50%);
  background-position: calc(100% - 8px) 50%, calc(100% - 4px) 50%;
  background-size: 4px 4px, 4px 4px;
  background-repeat: no-repeat;
  flex-shrink: 0;
}
.metronome__timesig:focus { outline: none; border-color: var(--accent); }

.metronome__vol-icon {
  font-size: 13px;
  color: var(--ink-soft);
  flex-shrink: 0;
}

/* =====================  RESPONSIVE  ===================== */
@media (max-width: 960px) {
  /* Collapse the sidebar to a fixed-height panel above the lesson. */
  .lesson-layout { grid-template-columns: 1fr; }
  .curriculum-sidebar {
    position: relative;
    top: 0;
    height: auto;
    max-height: 240px;
    border-right: none;
    border-bottom: 1px solid var(--rule);
    padding: 16px 20px 18px;
  }
}

@media (max-width: 720px) {
  .container { padding: 36px 20px; }
  .site-header__inner { padding: 14px 20px; flex-wrap: wrap; }
  .site-nav { gap: 16px; }
  .curriculum-hero h1 { font-size: 52px; }
  h1 { font-size: 44px; }
  .tracks-grid { grid-template-columns: 1fr; }
  .listening { margin-top: 36px; }
}