/* ==========================================================================
   英语听力单题精析 · 公共样式
   ========================================================================== */

:root {
  --bg: #eef2f9;
  --bg-2: #e3e9f5;
  --card: #ffffff;
  --ink: #1b2333;
  --ink-2: #4a5568;
  --ink-3: #7b8698;
  --line: #e3e8f0;
  --primary: #4b6bfb;
  --primary-2: #6f8bff;
  --primary-soft: #eef2ff;
  --accent: #ff8a4c;
  --ok: #12a06a;
  --ok-soft: #e6f7ef;
  --bad: #e5484d;
  --bad-soft: #fdecec;
  --mark: #fff3b8;
  --radius: 16px;
  --shadow-sm: 0 1px 2px rgba(23, 35, 66, .06), 0 2px 8px rgba(23, 35, 66, .05);
  --shadow: 0 2px 6px rgba(23, 35, 66, .06), 0 12px 32px rgba(23, 35, 66, .09);
  --sans: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 100% -10%, #dfe8ff 0%, transparent 60%),
    radial-gradient(900px 500px at -10% 110%, #ffe9dd 0%, transparent 55%),
    var(--bg);
  background-attachment: fixed;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

button { font-family: inherit; }

mark {
  background: linear-gradient(180deg, transparent 55%, var(--mark) 55%);
  color: inherit;
  padding: 0 2px;
  border-radius: 2px;
}

/* ---------- 顶栏 ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 10px 20px;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid rgba(227, 232, 240, .9);
}

.topbar .back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  color: var(--ink-2);
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fff;
  transition: .18s;
}
.topbar .back:hover { color: var(--primary); border-color: #c9d5ff; background: var(--primary-soft); text-decoration: none; }

.topbar h1 {
  font-size: 15px;
  font-weight: 650;
  margin: 0;
  letter-spacing: .01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.topbar .spacer { flex: 1; }
.topbar .meta { font-size: 12px; color: var(--ink-3); white-space: nowrap; }

/* ---------- 通用卡片 ---------- */
.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  border: 1px solid rgba(227, 232, 240, .8);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  line-height: 1;
  padding: 5px 9px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary);
  font-weight: 600;
  white-space: nowrap;
}
.chip.gray { background: #f1f4f9; color: var(--ink-2); }
.chip.ok { background: var(--ok-soft); color: var(--ok); }
.chip.bad { background: var(--bad-soft); color: var(--bad); }
.chip.warm { background: #fff2e9; color: #d9691f; }

/* ---------- 首页 ---------- */
.hero {
  max-width: 1040px;
  margin: 0 auto;
  padding: 64px 24px 28px;
}
.hero .kicker {
  font-size: 13px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--primary);
  font-weight: 700;
}
.hero h2 {
  font-size: clamp(28px, 4.2vw, 44px);
  line-height: 1.25;
  margin: 12px 0 14px;
  letter-spacing: -.01em;
}
.hero p.lead {
  font-size: 16px;
  color: var(--ink-2);
  max-width: 640px;
  margin: 0 0 8px;
}

.paper-list {
  max-width: 1040px;
  margin: 0 auto;
  padding: 28px 24px 80px;
  display: grid;
  gap: 16px;
}

.paper-card {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 22px 24px;
  color: var(--ink);
  transition: transform .18s cubic-bezier(.2,.8,.2,1), box-shadow .18s;
}
.paper-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  text-decoration: none;
}
.paper-card .ic {
  width: 48px; height: 48px;
  flex: 0 0 auto;
  border-radius: 14px;
  display: grid; place-items: center;
  font-size: 22px;
  background: linear-gradient(135deg, #e8eeff, #f5e9ff);
}
.paper-card .t { flex: 1; min-width: 0; }
.paper-card .t h3 { margin: 0 0 3px; font-size: 17px; }
.paper-card .t p { margin: 0; font-size: 13px; color: var(--ink-3); }
.paper-card .go {
  flex: 0 0 auto;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--primary-soft);
}

.feature-grid {
  max-width: 1040px;
  margin: 0 auto;
  padding: 8px 24px 20px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 14px;
}
.feature {
  padding: 18px 18px 16px;
  background: rgba(255,255,255,.72);
  border-radius: 14px;
  border: 1px solid rgba(227,232,240,.9);
}
.feature b { display: block; font-size: 14px; margin-bottom: 4px; }
.feature span { font-size: 12.5px; color: var(--ink-3); line-height: 1.55; display: block; }

.footnote {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 24px 60px;
  font-size: 12.5px;
  color: var(--ink-3);
}

/* ---------- 试卷页布局 ---------- */
.app {
  display: grid;
  grid-template-columns: 208px minmax(0, 1fr);
  gap: 20px;
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 20px 64px;
  align-items: start;
}

.side {
  position: sticky;
  top: 68px;
  padding: 14px;
}
.side h4 {
  margin: 0 0 8px;
  font-size: 11.5px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 700;
}
.side h4:not(:first-child) { margin-top: 16px; }
.nav-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
}
.nav-grid button {
  aspect-ratio: 1;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 9px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink-2);
  cursor: pointer;
  transition: .15s;
  position: relative;
  padding: 0;
}
.nav-grid button:hover { border-color: #c3d0ff; color: var(--primary); background: var(--primary-soft); }
.nav-grid button.on {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
  box-shadow: 0 4px 12px rgba(75, 107, 251, .35);
}
.nav-grid button.done::after {
  content: "";
  position: absolute;
  right: 3px; top: 3px;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--ok);
}
.nav-grid button.on.done::after { background: #fff; }
.nav-grid button.wrong::after { background: var(--bad); }

.side .legend {
  margin-top: 14px;
  font-size: 11.5px;
  color: var(--ink-3);
  line-height: 1.9;
  border-top: 1px dashed var(--line);
  padding-top: 10px;
}
.side .legend i {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  margin-right: 5px;
  vertical-align: 1px;
}
.side .reset {
  display: block;
  width: 100%;
  margin-top: 10px;
  padding: 7px 10px;
  border-radius: 9px;
  border: 1px dashed var(--line);
  background: #fff;
  font-size: 12px;
  color: var(--ink-3);
  cursor: pointer;
  transition: .15s;
}
.side .reset:hover { color: var(--bad); border-color: #f3cfd0; background: #fffafa; }

/* ---------- 题目区 ---------- */
.main { min-width: 0; display: flex; flex-direction: column; gap: 16px; }

.qhead {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
.qhead .no {
  font-size: 26px;
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1;
}
.qhead .no small { font-size: 13px; font-weight: 600; color: var(--ink-3); margin-left: 2px; }

.stem {
  margin: 10px 0 2px;
  font-size: clamp(17px, 1.4vw, 20px);
  font-weight: 650;
  line-height: 1.5;
  letter-spacing: .005em;
}
.stem-zh { font-size: 13px; color: var(--ink-3); margin: 4px 0 0; }

.opts { display: flex; flex-direction: column; gap: 9px; margin-top: 16px; }
.opt {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 15px;
  border-radius: 12px;
  border: 1.5px solid var(--line);
  background: #fff;
  cursor: pointer;
  text-align: left;
  transition: .15s;
  font-size: 15.5px;
  color: var(--ink);
  width: 100%;
}
.opt:hover { border-color: #c3d0ff; background: #fbfcff; }
.opt .k {
  flex: 0 0 auto;
  width: 25px; height: 25px;
  border-radius: 50%;
  display: grid; place-items: center;
  font-size: 13px;
  font-weight: 700;
  background: #f1f4f9;
  color: var(--ink-2);
  transition: .15s;
}
.opt .zh { margin-left: auto; font-size: 12.5px; color: var(--ink-3); white-space: nowrap; }
.opt .en { letter-spacing: .005em; }
.opt.sel { border-color: var(--primary); background: var(--primary-soft); }
.opt.sel .k { background: var(--primary); color: #fff; }
.opt.ok { border-color: var(--ok); background: var(--ok-soft); }
.opt.ok .k { background: var(--ok); color: #fff; }
.opt.bad { border-color: var(--bad); background: var(--bad-soft); }
.opt.bad .k { background: var(--bad); color: #fff; }
.opt .tick { margin-left: 6px; font-weight: 700; }
.opt.ok .tick { color: var(--ok); }
.opt.bad .tick { color: var(--bad); }

.feedback {
  margin-top: 12px;
  padding: 11px 14px;
  border-radius: 11px;
  font-size: 13.5px;
  display: flex;
  gap: 8px;
  align-items: flex-start;
  line-height: 1.6;
}
.feedback.ok { background: var(--ok-soft); color: #0b6b47; }
.feedback.bad { background: var(--bad-soft); color: #a3262a; }
.feedback b { font-weight: 700; }

/* ---------- 播放器 ---------- */
.player { padding: 14px 16px; position: relative; overflow: hidden; }
.player::before {
  content: "";
  position: absolute; inset: 0 0 auto 0; height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  opacity: .85;
}
.prow { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }

.pbtn {
  flex: 0 0 auto;
  width: 44px; height: 44px;
  border-radius: 50%;
  border: 0;
  background: var(--primary);
  color: #fff;
  display: grid; place-items: center;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(75, 107, 251, .35);
  transition: .15s;
}
.pbtn:hover { transform: scale(1.05); background: #3d5bf0; }
.pbtn svg { width: 19px; height: 19px; }

.track {
  flex: 1 1 240px;
  min-width: 180px;
  height: 30px;
  display: flex;
  align-items: center;
  cursor: pointer;
  position: relative;
  touch-action: none;
}
.track .rail {
  position: relative;
  width: 100%;
  height: 7px;
  border-radius: 99px;
  background: #e9edf5;
  overflow: hidden;
}
.track .fill {
  position: absolute; left: 0; top: 0; bottom: 0;
  width: 0;
  border-radius: 99px;
  background: linear-gradient(90deg, var(--primary-2), var(--primary));
}
.track .segs { position: absolute; inset: 0; }
.track .seg {
  position: absolute; top: 0; bottom: 0;
  background: rgba(23, 35, 66, .16);
  border-radius: 2px;
}
.track .knob {
  position: absolute;
  top: 50%;
  width: 13px; height: 13px;
  margin-left: -6.5px;
  border-radius: 50%;
  background: #fff;
  border: 2.5px solid var(--primary);
  transform: translateY(-50%);
  box-shadow: 0 1px 4px rgba(0,0,0,.18);
  left: 0;
  pointer-events: none;
}
.time { font-size: 12.5px; color: var(--ink-3); font-variant-numeric: tabular-nums; white-space: nowrap; }

.seg-tabs, .speed {
  display: inline-flex;
  background: #f3f6fb;
  border-radius: 9px;
  padding: 3px;
  gap: 2px;
}
.seg-tabs button, .speed button {
  border: 0;
  background: transparent;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--ink-2);
  padding: 5px 11px;
  border-radius: 7px;
  cursor: pointer;
  transition: .15s;
  white-space: nowrap;
}
.seg-tabs button:hover, .speed button:hover { color: var(--primary); }
.seg-tabs button.on, .speed button.on { background: #fff; color: var(--primary); box-shadow: 0 1px 3px rgba(23,35,66,.12); }

.toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12.5px;
  color: var(--ink-2);
  cursor: pointer;
  user-select: none;
  padding: 5px 10px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fff;
}
.toggle.on { border-color: var(--primary); color: var(--primary); background: var(--primary-soft); }
.toggle input { display: none; }

.player .hint {
  font-size: 12px;
  color: var(--ink-3);
  margin-top: 9px;
  padding-left: 2px;
}

/* ---------- 标签页 ---------- */
.tabs {
  display: flex;
  gap: 4px;
  padding: 4px;
  background: #eaeff8;
  border-radius: 12px;
  width: fit-content;
}
.tabs button {
  border: 0;
  background: transparent;
  padding: 8px 18px;
  border-radius: 9px;
  font-size: 14px;
  font-weight: 650;
  color: var(--ink-2);
  cursor: pointer;
  transition: .15s;
}
.tabs button.on { background: #fff; color: var(--ink); box-shadow: var(--shadow-sm); }
.tabs button:hover:not(.on) { color: var(--primary); }

.panel { padding: 20px 22px; display: none; }
.panel.on { display: block; }

.block + .block { margin-top: 22px; padding-top: 20px; border-top: 1px dashed var(--line); }
.block > h5 {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 10px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .01em;
}
.block > h5 .dot {
  width: 18px; height: 18px;
  border-radius: 6px;
  display: grid; place-items: center;
  font-size: 11px;
  background: var(--primary-soft);
  color: var(--primary);
  flex: 0 0 auto;
}

.loc { display: flex; flex-direction: column; gap: 8px; }
.loc-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 11px 13px;
  border-radius: 11px;
  background: linear-gradient(180deg, #fbfcff, #f6f9ff);
  border: 1px solid #e4ebfb;
  cursor: pointer;
  transition: .15s;
  font-size: 14.5px;
  line-height: 1.6;
}
.loc-item:hover { border-color: #c3d0ff; background: #f4f7ff; }
.loc-item .spk {
  flex: 0 0 auto;
  width: 20px; height: 20px;
  border-radius: 6px;
  display: grid; place-items: center;
  font-size: 11px; font-weight: 700;
  background: #e9eefc; color: #5a6b96;
  margin-top: 2px;
}
.loc-item .play {
  flex: 0 0 auto;
  font-size: 11.5px;
  color: var(--primary);
  font-weight: 600;
  margin-left: auto;
  opacity: 0;
  transition: .15s;
  white-space: nowrap;
}
.loc-item:hover .play { opacity: 1; }

.steps { margin: 0; padding: 0; list-style: none; counter-reset: s; }
.steps li {
  position: relative;
  padding: 0 0 12px 30px;
  counter-increment: s;
  font-size: 14.5px;
  color: var(--ink-2);
  line-height: 1.72;
}
.steps li::before {
  content: counter(s);
  position: absolute;
  left: 0; top: 3px;
  width: 19px; height: 19px;
  border-radius: 50%;
  background: #eef2ff;
  color: var(--primary);
  font-size: 11px;
  font-weight: 700;
  display: grid; place-items: center;
}
.steps li:last-child { padding-bottom: 0; }
.steps li b, .block b { color: var(--ink); font-weight: 700; }

.traps { display: flex; flex-direction: column; gap: 9px; }
.trap {
  display: flex;
  gap: 10px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-2);
  padding: 10px 12px;
  border-radius: 10px;
  background: #fdfbfa;
  border: 1px solid #f4e7e1;
}
.trap .k {
  flex: 0 0 auto;
  width: 20px; height: 20px;
  border-radius: 6px;
  background: #ffe9de;
  color: #c4521f;
  font-size: 12px; font-weight: 800;
  display: grid; place-items: center;
  margin-top: 1px;
}

.answer-line {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 14px;
  border-radius: 12px;
  background: linear-gradient(90deg, #eafaf2, #f3fbff);
  border: 1px solid #cdeede;
  margin-bottom: 4px;
}
.answer-line .badge {
  flex: 0 0 auto;
  width: 34px; height: 34px;
  border-radius: 10px;
  background: var(--ok);
  color: #fff;
  font-weight: 800;
  font-size: 17px;
  display: grid; place-items: center;
}
.answer-line .txt { font-size: 14px; color: #0b6b47; line-height: 1.55; }

.tipbox {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-2);
  background: #fffaf0;
  border: 1px solid #f6e6c8;
  border-radius: 11px;
  padding: 13px 15px;
}

.words { display: flex; flex-wrap: wrap; gap: 8px; }
.word {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 6px 11px;
  border-radius: 9px;
  background: #f5f7fc;
  border: 1px solid #e8ecf5;
  font-size: 13px;
}
.word b { font-weight: 650; color: var(--ink); }
.word span { color: var(--ink-3); font-size: 12.5px; }

/* ---------- 原文 ---------- */
.tr-tools {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--line);
}
.tr-tools .grow { flex: 1; }

.line {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 10px;
  padding: 7px 8px 7px 6px;
  border-radius: 11px;
  transition: background .18s;
}
.line:hover { background: #f8faff; }
.line.live { background: #eef3ff; }
.line .who {
  width: 26px; height: 26px;
  border-radius: 8px;
  display: grid; place-items: center;
  font-size: 11.5px; font-weight: 800;
  margin-top: 2px;
  letter-spacing: .02em;
  cursor: pointer;
  transition: transform .15s, box-shadow .15s;
}
.line .who:hover { transform: scale(1.12); box-shadow: 0 2px 8px rgba(23,35,66,.18); }
.line .who.M { background: #e7eeff; color: #3457c4; }
.line .who.W { background: #ffeae0; color: #c0552a; }
.line .who.S { background: #eae6ff; color: #5b45c4; }

.sent {
  display: block;
  font-size: 15px;
  line-height: 1.62;
  color: var(--ink);
  border-radius: 6px;
  padding: 1px 5px;
  margin: -1px -5px;
  cursor: pointer;
  transition: background .15s, box-shadow .15s;
}
.sent:hover { background: #e9efff; }
.sent.live { background: #dfe8ff; box-shadow: inset 2px 0 0 var(--primary); }
.sent.hl { background: #fff5cf; box-shadow: inset 2px 0 0 #e8b21f; }
.sent .zh {
  display: block;
  font-size: 12.5px;
  color: var(--ink-3);
  line-height: 1.5;
  margin-top: 2px;
}
body.hide-zh .sent .zh { display: none; }

.line .lnum {
  font-size: 11px;
  color: #b9c2d2;
  font-variant-numeric: tabular-nums;
  margin-top: 3px;
}

/* ---------- 页脚导航 ---------- */
.pager {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 2px 0;
}
.pager button {
  flex: 1;
  padding: 12px 16px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink-2);
  cursor: pointer;
  transition: .15s;
  text-align: left;
}
.pager button:hover:not(:disabled) { border-color: #c3d0ff; color: var(--primary); background: #fbfcff; }
.pager button:disabled { opacity: .45; cursor: default; }
.pager button.next { text-align: right; }
.pager .kbd {
  font-size: 11px;
  color: var(--ink-3);
  background: #f1f4f9;
  border-radius: 5px;
  padding: 1px 5px;
  margin: 0 3px;
}

@media (max-width: 860px) {
  .app { grid-template-columns: 1fr; padding: 14px 14px 48px; }
  .side { position: static; order: -1; }
  .side h4:not(:first-child) { margin-top: 12px; }
  .nav-grid { grid-template-columns: repeat(10, 1fr); }
  .side .legend { display: none; }
  .panel { padding: 16px 14px; }
  .opt .zh { display: none; }
  .topbar .meta { display: none; }
  .hero { padding: 36px 18px 20px; }
  .paper-list, .feature-grid, .footnote { padding-left: 18px; padding-right: 18px; }
  .tr-tools .grow { display: none; }
  .pager button .kbd { display: none; }
}

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