/* Endurance Audiobooks: a calm reading library. Navy and sky blue, light and dark. */
:root {
  color-scheme: light;
  --bg: #f5f8fc;
  --surface: #ffffff;
  --surface-2: #edf3fb;
  --ink: #14223a;
  --ink-2: #4f5d73;
  --line: #d9e3f0;
  --brand: #1e3a6e;
  --brand-ink: #18305c;
  --soft: #e3edfb;
  --soft-2: #b9cdeb;
  --accent: #2f6fb5;
  --focus: #2f6fb5;
  --warn: #8a4b00;
  --warn-bg: #fff3e0;
  --ok: #1f6b49;
  --shadow: 0 1px 2px rgba(15, 35, 70, 0.06), 0 8px 24px rgba(15, 35, 70, 0.06);
  --radius: 18px;
  --reading-size: 1.15rem;
  --serif: Charter, 'Bitstream Charter', 'Sitka Text', Cambria, Georgia, serif;
  --sans: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0e1626;
    --surface: #152038;
    --surface-2: #1b2a47;
    --ink: #ecf2fb;
    --ink-2: #a9b8cf;
    --line: #263a5c;
    --brand: #9cc3f5;
    --brand-ink: #c4dbfa;
    --soft: #1f3256;
    --soft-2: #35507f;
    --accent: #7fb3f0;
    --focus: #9cc3f5;
    --warn: #ffc27a;
    --warn-bg: #3a2a12;
    --ok: #8fe0b8;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.25);
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.55 var(--sans); min-height: 100vh; }
a { color: var(--brand); }
a:hover { color: var(--accent); }
button, input, select, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; border-radius: 6px; }
[hidden] { display: none !important; }
.skip { position: absolute; left: 12px; top: -60px; padding: 10px 16px; background: var(--surface); color: var(--ink); border-radius: 10px; z-index: 10; }
.skip:focus { top: 12px; }
.wrap { max-width: 1160px; margin: 0 auto; padding: 0 20px; }
@media (max-width: 520px) { .wrap { padding: 0 16px; } }

/* Site bar */
.sitebar { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 68px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); text-decoration: none; font-weight: 800; letter-spacing: 0.12em; font-size: 0.78rem; line-height: 1.15; }
.brand-logo { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 11px; background: var(--brand); color: var(--bg); font: 700 1.25rem/1 Georgia, serif; letter-spacing: 0; }
.brand small { display: block; font-size: 0.66rem; letter-spacing: 0.2em; color: var(--ink-2); font-weight: 700; }
.sitebar nav { display: flex; gap: 6px; flex-wrap: wrap; justify-content: flex-end; }
.sitebar nav a { padding: 7px 12px; border-radius: 999px; text-decoration: none; color: var(--ink-2); font-weight: 650; font-size: 0.9rem; }
.sitebar nav a:hover { background: var(--surface-2); color: var(--ink); }
.sitebar nav a[aria-current='page'] { background: var(--soft); color: var(--brand-ink); }
@media (max-width: 560px) { .sitebar { flex-wrap: wrap; padding: 10px 0; } .sitebar nav { justify-content: flex-start; } }

/* Home */
.hero { padding: 56px 0 28px; }
.hero h1 { margin: 0; font: 700 clamp(2.2rem, 5vw, 3.4rem)/1.05 var(--serif); letter-spacing: -0.02em; color: var(--brand-ink); }
.tagline { margin: 12px 0 0; font-size: clamp(1.1rem, 2.4vw, 1.35rem); color: var(--ink-2); }
.tagline span { white-space: nowrap; }
.section-title { margin: 28px 0 14px; font-size: 1.05rem; color: var(--ink-2); font-weight: 700; letter-spacing: 0.02em; }
.grade-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; padding-bottom: 48px; }
.grade-card { display: flex; flex-direction: column; gap: 10px; padding: 22px; min-height: 180px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow); color: var(--ink); text-decoration: none; transition: border-color 0.15s; }
.grade-card:hover { border-color: var(--soft-2); color: var(--ink); }
.grade-badge { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 16px; background: var(--soft); color: var(--brand-ink); font: 700 1.6rem/1 var(--serif); }
.grade-card h2 { margin: 4px 0 0; font: 700 1.35rem/1.2 var(--serif); }
.grade-card .count { margin: 0; color: var(--ink-2); }
.grade-card .units { margin: 0; color: var(--ink-2); font-size: 0.92rem; }
.grade-card .go { margin-top: auto; font-weight: 700; color: var(--brand); }

/* Grade library */
.page-head { padding: 34px 0 8px; }
.page-head h1 { margin: 6px 0 0; font: 700 clamp(1.8rem, 4vw, 2.5rem)/1.1 var(--serif); color: var(--brand-ink); }
.back-link { display: inline-flex; gap: 2px; font-weight: 650; text-decoration: none; padding: 6px 0; }
.unit { padding: 10px 0 18px; }
.unit h2 { margin: 18px 0 12px; font-size: 1.15rem; display: flex; align-items: center; gap: 10px; }
.unit h2::before { content: ''; width: 10px; height: 10px; border-radius: 50%; background: var(--accent); }
.book-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr)); gap: 16px; }
.book { display: grid; grid-template-columns: 96px 1fr; gap: 16px; padding: 16px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow); }
.cover { position: relative; aspect-ratio: 3 / 4; border-radius: 10px; overflow: hidden; background: linear-gradient(160deg, #2f6fb5, #1e3a6e 70%); color: #fff; display: flex; flex-direction: column; justify-content: space-between; padding: 10px 9px; }
.cover::after { content: ''; position: absolute; left: 7px; top: 0; bottom: 0; width: 2px; background: rgba(255, 255, 255, 0.22); }
.cover .cover-unit { font-size: 0.6rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; opacity: 0.85; padding-left: 6px; }
.cover .cover-mark { font: 700 2rem/1 var(--serif); padding-left: 6px; }
.book h3 { margin: 0; font: 700 1.12rem/1.25 var(--serif); }
.book .meta { margin: 4px 0 0; color: var(--ink-2); font-size: 0.88rem; }
.book .desc { margin: 8px 0 0; font-size: 0.94rem; }
.book .facts { margin: 8px 0 0; color: var(--ink-2); font-size: 0.86rem; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 10px 18px; border-radius: 999px; border: 1px solid transparent; background: var(--brand); color: var(--bg); font-weight: 700; text-decoration: none; cursor: pointer; }
.btn:hover { background: var(--accent); color: var(--bg); }
.btn.secondary { background: var(--surface); color: var(--brand); border-color: var(--soft-2); }
.btn.secondary:hover { background: var(--surface-2); }
.btn.danger { background: transparent; color: #b4232f; border-color: #e7b8bd; }
.btn:disabled { opacity: 0.5; cursor: default; }
.book .btn { margin-top: 12px; }
.empty { padding: 28px; border-radius: var(--radius); background: var(--surface); border: 1px dashed var(--soft-2); color: var(--ink-2); font-size: 1.05rem; }
.notice { padding: 14px 16px; border-radius: 12px; background: var(--warn-bg); color: var(--warn); }
.footer { padding: 30px 0 40px; color: var(--ink-2); font-size: 0.85rem; border-top: 1px solid var(--line); margin-top: 30px; }
@media (max-width: 420px) { .book { grid-template-columns: 72px 1fr; gap: 12px; } }

/* Reader */
.reader { padding-bottom: 48px; }
.reading-head { padding: 26px 0 6px; }
.eyebrow { margin: 6px 0 0; color: var(--accent); font-weight: 750; font-size: 0.82rem; letter-spacing: 0.08em; text-transform: uppercase; }
.reading-head h1 { margin: 6px 0 0; font: 700 clamp(1.6rem, 3.6vw, 2.35rem)/1.15 var(--serif); color: var(--brand-ink); max-width: 30ch; }
.reading-desc { margin: 10px 0 0; color: var(--ink-2); max-width: 70ch; }
.now-line { margin: 10px 0 0; color: var(--ink-2); }
.now-line strong { color: var(--ink); }
.reader-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 18px; padding: 12px 0 16px; }
.tool-group { display: inline-flex; align-items: center; gap: 6px; }
.tool-label { color: var(--ink-2); font-size: 0.9rem; margin-right: 2px; }
.tool { display: inline-flex; align-items: baseline; gap: 1px; min-width: 48px; min-height: 44px; justify-content: center; padding: 6px 10px; border-radius: 12px; border: 1px solid var(--line); background: var(--surface); cursor: pointer; font-weight: 700; }
.tool:disabled { opacity: 0.4; cursor: default; }
.a-small { font-size: 0.85rem; }
.a-large { font-size: 1.2rem; }
.segmented { display: inline-flex; padding: 3px; border-radius: 999px; background: var(--surface-2); border: 1px solid var(--line); }
.seg { min-height: 40px; padding: 6px 16px; border: 0; border-radius: 999px; background: transparent; color: var(--ink-2); font-weight: 700; cursor: pointer; }
.seg[aria-pressed='true'] { background: var(--surface); color: var(--brand-ink); box-shadow: var(--shadow); }
.reader-layout { display: grid; grid-template-columns: minmax(0, 1fr) 360px; grid-template-areas: 'passage side'; gap: 28px; align-items: start; }
.side { grid-area: side; position: sticky; top: 14px; display: grid; gap: 14px; }
.passage { grid-area: passage; }
@media (max-width: 899px) {
  .reader-layout { grid-template-columns: minmax(0, 1fr); grid-template-areas: 'side' 'passage'; gap: 18px; }
  .side { position: static; }
}
.player, .guide { padding: 18px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow); }
.player-title { margin: 0 0 10px; font-size: 0.82rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-2); }
.parts { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 8px; }
.part-btn { display: grid; gap: 1px; text-align: left; min-height: 52px; padding: 8px 12px; border-radius: 12px; border: 1px solid var(--line); background: var(--surface-2); cursor: pointer; }
.part-btn .part-name { font-weight: 750; }
.part-btn .part-range { font-size: 0.82rem; color: var(--ink-2); }
.part-btn[aria-pressed='true'] { background: var(--brand); border-color: var(--brand); color: var(--bg); }
.part-btn[aria-pressed='true'] .part-range { color: inherit; opacity: 0.85; }
.controls { display: flex; align-items: center; justify-content: center; gap: 14px; margin: 18px 0 8px; }
.controls button { display: inline-grid; place-items: center; border: 1px solid var(--line); background: var(--surface); border-radius: 50%; cursor: pointer; color: var(--brand-ink); }
.controls button:disabled { opacity: 0.4; cursor: default; }
.controls svg { width: 24px; height: 24px; fill: currentColor; }
.ctl { position: relative; width: 52px; height: 52px; }
.ctl-num { position: absolute; bottom: 5px; font-size: 0.6rem; font-weight: 800; }
.play { width: 76px; height: 76px; background: var(--brand) !important; border-color: var(--brand) !important; color: var(--bg) !important; }
.play svg { width: 36px; height: 36px; }
.progress { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 12px; }
.seek { width: 100%; height: 32px; accent-color: var(--accent); cursor: pointer; }
.clock { font-variant-numeric: tabular-nums; color: var(--ink-2); font-size: 0.92rem; }
.player-foot { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 10px; margin-top: 8px; }
.speed-label { display: inline-flex; align-items: center; gap: 8px; color: var(--ink-2); font-weight: 650; }
.speed { min-height: 40px; padding: 6px 10px; border-radius: 10px; border: 1px solid var(--line); background: var(--surface); }
.next-part { min-height: 44px; padding: 8px 16px; border-radius: 999px; border: 0; background: var(--soft); color: var(--brand-ink); font-weight: 750; cursor: pointer; }
.msg-row { display: flex; flex-wrap: wrap; gap: 4px 10px; align-items: baseline; }
.audio-msg { margin: 8px 0 0; color: var(--ink-2); }
.audio-msg:empty { display: none; }
.link-btn { padding: 4px 0; border: 0; background: none; color: var(--brand); font-weight: 700; text-decoration: underline; cursor: pointer; }
.listen-box { display: none; }
.is-listen .listen-box { display: block; margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); }
.listen-note { margin: 0 0 4px; }
.is-listen .passage { display: none; }
.is-listen .reader-layout { grid-template-columns: minmax(0, 560px); grid-template-areas: 'side'; justify-content: center; }
.is-listen .side { position: static; }
.player.is-empty p { margin: 0; color: var(--ink-2); }

.passage { font: var(--reading-size) / 1.8 var(--serif); max-width: 72ch; }
.para { display: grid; grid-template-columns: 2.6em 1fr; gap: 0.6em; margin: 0 0 1.1em; padding: 0.35em 0.6em 0.35em 0; border-radius: 10px; border-left: 4px solid transparent; }
.para.in-part { border-left-color: var(--soft-2); background: color-mix(in srgb, var(--soft) 45%, transparent); }
.para-num { font: 800 0.82em/2.2 var(--sans); color: var(--accent); text-align: right; user-select: none; }
.para-text { overflow-wrap: anywhere; }
.part-marker { display: inline-flex; align-items: center; gap: 4px; margin: 0.6em 0 0.7em 3.2em; padding: 6px 14px; min-height: 40px; border-radius: 999px; border: 1px solid var(--soft-2); background: var(--surface); color: var(--brand-ink); font: 700 0.9rem/1.2 var(--sans); cursor: pointer; }
.part-marker .part-range { color: var(--ink-2); font-weight: 600; }
@media (max-width: 520px) { .para { grid-template-columns: 2em 1fr; gap: 0.4em; } .part-marker { margin-left: 2.4em; } }

.guide summary { cursor: pointer; font-weight: 750; font-size: 1rem; min-height: 32px; display: flex; align-items: center; }
.guide-lead { margin: 10px 0 6px; color: var(--ink-2); font-size: 0.94rem; }
.symbols { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.symbols li { display: flex; align-items: center; gap: 12px; }
.sym { display: grid; place-items: center; width: 36px; height: 36px; border-radius: 10px; background: var(--soft); color: var(--brand-ink); font: 800 1.2rem/1 var(--sans); flex: none; }
.golden { margin: 12px 0 0; padding: 10px 12px; border-radius: 12px; background: var(--surface-2); font-size: 0.94rem; }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; scroll-behavior: auto !important; } }