/* ==========================================================================
   应知应会答题 —— 样式表
   移动端优先，>=1000px 时答题页变为「左题目 + 右侧答题卡」两栏布局。
   ========================================================================== */

/* 页面底色统一用白色，手机和电脑共用这一套变量，不做各自的配色。
   主题固定为浅色，不会跟着手机的系统深色模式变暗。 */
:root {
  --topbar-h: 56px;
  /* 让浏览器只用浅色渲染原生控件（输入框、滚动条、下拉框），
     否则安卓 / iOS 在深色系统下会自己把这些控件染深，
     出现「页面是白的、输入框是黑的」这种割裂感 */
  color-scheme: light;
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-2: #f6f8fb;
  --border: #e1e6ee;
  --border-strong: #cbd5e1;
  --text: #0f172a;
  --text-soft: #475569;
  --text-muted: #7c8899;
  --primary: #2563eb;
  --primary-strong: #1d4ed8;
  --primary-soft: #eff5ff;
  --success: #15803d;
  --success-soft: #eefaf1;
  --danger: #dc2626;
  --danger-soft: #fdf0f0;
  --warning: #b45309;
  --warning-soft: #fff8eb;
  --radius-lg: 18px;
  --radius: 12px;
  --radius-sm: 9px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .05), 0 6px 20px rgba(15, 23, 42, .06);
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, .07);
}

/* 主题固定为浅色：手机和电脑都用同一套变量，不会因为系统是深色模式就变暗。
   如果以后要加深色模式，在这里补一段 html[data-theme="dark"] 的变量覆盖即可。 */

* { box-sizing: border-box; }

/* 作者样式里的 display 会盖掉 hidden 属性的默认表现，这里统一兜底 */
[hidden] { display: none !important; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { margin: 0; font-weight: 700; letter-spacing: -.01em; }
a { color: inherit; text-decoration: none; }

/* ------------------------------- 顶栏 ------------------------------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--topbar-h);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: saturate(1.6) blur(10px);
  border-bottom: 1px solid var(--border);
}

.topbar__inner {
  max-width: 1180px;
  height: 100%;
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand { display: flex; align-items: center; gap: 9px; min-width: 0; }

/* 顶栏文字一律不换行，否则窄屏上「应知应会答题」会被折成两行 */
.brand__text strong,
.brand__text small,
.topnav a { white-space: nowrap; }

.brand__mark {
  flex: none;
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--primary), #7c3aed);
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  display: grid;
  place-items: center;
}

.brand__text { display: flex; flex-direction: column; line-height: 1.15; min-width: 0; }
.brand__text strong { font-size: 15px; }
.brand__text small { font-size: 11px; color: var(--text-muted); }

.topnav { display: flex; gap: 4px; }
.topnav a {
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 14px;
  color: var(--text-soft);
}
.topnav a:hover { background: var(--surface-2); color: var(--text); }
.topnav a.is-active { background: var(--primary-soft); color: var(--primary-strong); font-weight: 600; }

/* ------------------------------- 布局 ------------------------------- */

#main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 18px 16px 40px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 18px;
  margin-bottom: 16px;
}

.card__title { font-size: 16px; margin-bottom: 14px; }

/* ------------------------------- 首页 ------------------------------- */

.hero {
  padding: 8px 4px 18px;
  text-align: center;
}
.hero__title {
  font-size: 26px;
  background: linear-gradient(120deg, var(--primary), #7c3aed);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero__sub { margin: 10px auto 0; max-width: 620px; color: var(--text-soft); font-size: 14px; }
.hero__sub b { color: var(--primary-strong); font-size: 15px; }

.card--start { border-color: color-mix(in srgb, var(--primary) 35%, var(--border)); }

.field { display: block; }
.field__label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 7px; }
.field__label em { color: var(--danger); font-style: normal; }

.field__input {
  width: 100%;
  padding: 12px 14px;
  font: inherit;
  font-size: 16px; /* iOS 上小于 16px 会触发聚焦缩放 */
  color: var(--text);
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  transition: border-color .15s, background .15s;
}
.field__input:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--surface);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 18%, transparent);
}
.field__input.is-invalid { border-color: var(--danger); }

.field__error { margin: 8px 0 0; font-size: 13px; color: var(--danger); }

.resume {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: var(--radius);
  background: var(--warning-soft);
  border: 1px dashed color-mix(in srgb, var(--warning) 45%, transparent);
}
.resume__info { display: flex; flex-direction: column; min-width: 0; }
.resume__label { font-size: 13px; font-weight: 600; color: var(--warning); }
.resume__detail { font-size: 13px; color: var(--text-soft); }

.rules { list-style: none; margin: 0 0 14px; padding: 0; display: grid; gap: 9px; }
.rules__item { display: flex; gap: 9px; font-size: 14px; color: var(--text-soft); }
.rules__dot {
  flex: none;
  width: 6px;
  height: 6px;
  margin-top: 9px;
  border-radius: 50%;
  background: var(--primary);
}

/* ------------------------------- 按钮 ------------------------------- */

.btn {
  appearance: none;
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 11px 18px;
  font: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background .15s, border-color .15s, color .15s, transform .08s;
  white-space: nowrap;
}
.btn:active { transform: scale(.985); }
.btn:focus-visible { outline: 3px solid color-mix(in srgb, var(--primary) 40%, transparent); outline-offset: 2px; }

.btn--primary { background: var(--primary); color: #fff; }
.btn--primary:hover { background: var(--primary-strong); }

.btn--ghost { background: var(--surface); color: var(--text-soft); border-color: var(--border-strong); }
.btn--ghost:hover { border-color: var(--primary); color: var(--primary-strong); background: var(--primary-soft); }

.btn--block { width: 100%; }
.btn--sm { padding: 7px 13px; font-size: 13.5px; border-radius: var(--radius-sm); }
.btn:disabled { opacity: .55; cursor: not-allowed; transform: none; }

/* ------------------------------- 表格 ------------------------------- */

.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }

.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th, .table td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--border); }
.table thead th { font-size: 12.5px; color: var(--text-muted); font-weight: 600; background: var(--surface-2); }
.table tbody tr:last-child td { border-bottom: none; }
.table--rules td:last-child, .table--rules th:last-child { text-align: right; font-variant-numeric: tabular-nums; }
.table--rules tfoot th, .table--rules tfoot td { font-weight: 700; border-top: 2px solid var(--border); }
.table--rules tfoot td:last-child { color: var(--primary-strong); font-size: 16px; }
.table__num { font-variant-numeric: tabular-nums; }

/* ------------------------------- 答题页 ------------------------------- */

.exam-bar {
  position: sticky;
  top: var(--topbar-h);
  z-index: 30;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  padding: 11px 14px;
  margin: -18px -16px 14px;
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  backdrop-filter: saturate(1.6) blur(10px);
  border-bottom: 1px solid var(--border);
}

.exam-bar__info { display: flex; align-items: center; gap: 10px; min-width: 0; }
.exam-bar__name { font-weight: 700; font-size: 15px; white-space: nowrap; }

.exam-bar__timer {
  font-variant-numeric: tabular-nums;
  font-size: 13.5px;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary-strong);
}
.exam-bar__timer.is-warning { background: var(--warning-soft); color: var(--warning); }
.exam-bar__timer.is-danger { background: var(--danger-soft); color: var(--danger); animation: pulse 1s infinite; }

@keyframes pulse { 50% { opacity: .45; } }

.exam-bar__progress { display: flex; align-items: center; gap: 9px; flex: 1 1 160px; min-width: 140px; }
.exam-bar__count { font-size: 13px; color: var(--text-muted); font-variant-numeric: tabular-nums; white-space: nowrap; }

.progress { flex: 1; height: 7px; border-radius: 999px; background: var(--border); overflow: hidden; }
.progress__bar {
  height: 100%;
  width: 0;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--primary), #7c3aed);
  transition: width .25s ease;
}

.exam-bar__actions { display: none; gap: 8px; margin-left: auto; }

.exam-layout { display: block; }

.exam-main { min-width: 0; }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 12px;
  margin: 22px 0 12px;
  padding: 0 2px;
}
.section-head:first-child { margin-top: 4px; }
.section-head__title { font-size: 16.5px; }
.section-head__meta { font-size: 13px; color: var(--text-muted); }

/* ------------------------------- 题目卡片 ------------------------------- */

.q-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  padding: 15px;
  margin-bottom: 12px;
  scroll-margin-top: 140px;
}
.q-card.is-active { border-color: var(--primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 15%, transparent); }

.q-card__head { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }

.q-no {
  display: inline-grid;
  place-items: center;
  min-width: 27px;
  height: 27px;
  padding: 0 7px;
  border-radius: 8px;
  background: var(--primary);
  color: #fff;
  font-size: 13.5px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.q-badge {
  font-size: 11.5px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.q-stem {
  margin: 11px 0 13px;
  font-size: 15px;
  line-height: 1.75;
  font-weight: 500;
  word-break: break-word;
}

.q-options { display: grid; gap: 8px; }

.q-option {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 10px 12px;
  min-height: 46px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface-2);
  cursor: pointer;
  transition: border-color .15s, background .15s;
  -webkit-tap-highlight-color: transparent;
}
.q-option:hover { border-color: var(--primary); background: var(--primary-soft); }
.q-option.is-checked {
  border-color: var(--primary);
  background: var(--primary-soft);
  box-shadow: inset 0 0 0 1px var(--primary);
}

.q-option__key {
  flex: none;
  width: 25px;
  height: 25px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 1.5px solid var(--border-strong);
  background: var(--surface);
  color: var(--text-soft);
  font-size: 12.5px;
  font-weight: 700;
  transition: background .15s, color .15s, border-color .15s;
}
.q-option[data-type="multiple"] .q-option__key { border-radius: 7px; }
.q-option.is-checked .q-option__key { background: var(--primary); border-color: var(--primary); color: #fff; }

.q-option__text { flex: 1; font-size: 14.5px; line-height: 1.65; word-break: break-word; padding-top: 1px; }

/* 判卷后的选项配色 */
.q-card.is-review .q-option { cursor: default; }
.q-card.is-review .q-option:hover { border-color: var(--border); background: var(--surface-2); }

.q-option.is-correct {
  border-color: var(--success);
  background: var(--success-soft);
  box-shadow: inset 0 0 0 1px var(--success);
}
.q-option.is-correct .q-option__key { background: var(--success); border-color: var(--success); color: #fff; }

.q-option.is-missed { border-style: dashed; }

.q-option.is-wrong {
  border-color: var(--danger);
  background: var(--danger-soft);
  box-shadow: inset 0 0 0 1px var(--danger);
}
.q-option.is-wrong .q-option__key { background: var(--danger); border-color: var(--danger); color: #fff; }

.q-option__mark { flex: none; align-self: center; font-size: 13px; font-weight: 700; }
.q-option.is-correct .q-option__mark { color: var(--success); }
.q-option.is-wrong .q-option__mark { color: var(--danger); }

.q-foot {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-top: 12px;
  padding-top: 11px;
  border-top: 1px dashed var(--border);
  font-size: 13px;
}
.q-foot__item { display: flex; gap: 6px; align-items: center; }
.q-foot__label { color: var(--text-muted); }
.q-foot__value { font-weight: 700; }
.q-foot__value.ok { color: var(--success); }
.q-foot__value.bad { color: var(--danger); }
.q-foot__value.mid { color: var(--warning); }

/* ------------------------------- 答题卡 ------------------------------- */

.palette {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 60;
  max-height: 78vh;
  overflow-y: auto;
  padding: 14px 16px calc(16px + env(safe-area-inset-bottom));
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-radius: 18px 18px 0 0;
  box-shadow: 0 -8px 30px rgba(15, 23, 42, .16);
  transform: translateY(105%);
  transition: transform .24s cubic-bezier(.32, .72, 0, 1);
}
.palette.is-open { transform: translateY(0); }

.palette__head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.palette__head h3 { font-size: 15px; }
.palette__close {
  border: none;
  background: var(--surface-2);
  color: var(--text-soft);
  width: 30px;
  height: 30px;
  border-radius: 50%;
  font-size: 20px;
  line-height: 1;
  cursor: pointer;
}

.palette__group { margin-bottom: 14px; }
.palette__group:last-of-type { margin-bottom: 12px; }
.palette__title { font-size: 12.5px; color: var(--text-muted); margin-bottom: 7px; }

.palette__grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(40px, 1fr)); gap: 7px; }

.palette__cell {
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border);
  background: var(--surface-2);
  color: var(--text-muted);
  font-size: 13.5px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  cursor: pointer;
  transition: background .12s, border-color .12s, color .12s;
}
.palette__cell.is-done { background: var(--primary-soft); border-color: var(--primary); color: var(--primary-strong); }
.palette__cell.is-current { outline: 2px solid var(--primary); outline-offset: 1px; }
.palette__cell:hover { border-color: var(--primary); }

.palette__legend { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 12px; font-size: 12.5px; color: var(--text-muted); }
.palette__legend span { display: flex; align-items: center; gap: 5px; }
.palette__legend i { width: 11px; height: 11px; border-radius: 4px; border: 1.5px solid var(--border-strong); background: var(--surface-2); }
.palette__legend .is-done i { background: var(--primary-soft); border-color: var(--primary); }

/* 移动端底部操作条 */
.exam-footbar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 45;
  display: flex;
  gap: 10px;
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  background: color-mix(in srgb, var(--surface) 94%, transparent);
  backdrop-filter: blur(10px);
  border-top: 1px solid var(--border);
}
.exam-footbar .btn { flex: 1; }
.exam-footbar .btn--ghost { flex: 0 0 34%; }

/* ------------------------------- 成绩页 ------------------------------- */

.score-card {
  border-radius: var(--radius-lg);
  padding: 24px 18px;
  text-align: center;
  color: #fff;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--primary), #7c3aed);
  box-shadow: 0 12px 32px color-mix(in srgb, var(--primary) 32%, transparent);
}
.score-card.is-mid { background: linear-gradient(135deg, #d97706, #dc2626); box-shadow: 0 12px 32px rgba(217, 119, 6, .3); }
.score-card__label { font-size: 14px; opacity: .9; }
.score-card__value { font-size: 52px; font-weight: 800; line-height: 1.1; font-variant-numeric: tabular-nums; }
.score-card__value small { font-size: 20px; font-weight: 600; opacity: .85; }
.score-card__verdict { display: inline-block; margin-top: 6px; padding: 3px 14px; border-radius: 999px; background: rgba(255, 255, 255, .2); font-size: 13.5px; font-weight: 600; }
.score-card__meta { margin-top: 14px; display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 20px; font-size: 13px; opacity: .92; }

.stat-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; margin-bottom: 16px; }
.stat {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 13px 14px;
  box-shadow: var(--shadow-sm);
}
.stat__value { font-size: 22px; font-weight: 800; font-variant-numeric: tabular-nums; line-height: 1.25; }
.stat__value small { font-size: 13px; font-weight: 600; color: var(--text-muted); margin-left: 2px; }
.stat__label { font-size: 12.5px; color: var(--text-muted); }
.stat--ok .stat__value { color: var(--success); }
.stat--bad .stat__value { color: var(--danger); }
.stat--mid .stat__value { color: var(--warning); }

.section-bars { display: grid; gap: 13px; }
.section-bar__top { display: flex; justify-content: space-between; font-size: 13.5px; margin-bottom: 5px; }
.section-bar__title { font-weight: 600; }
.section-bar__value { color: var(--text-muted); font-variant-numeric: tabular-nums; }
.section-bar__track { height: 8px; border-radius: 999px; background: var(--border); overflow: hidden; }
.section-bar__fill { height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--primary), #7c3aed); transition: width .6s ease; }
.section-bar__fill.is-mid { background: linear-gradient(90deg, #d97706, #dc2626); }
.section-bar__note { font-size: 12.5px; color: var(--text-muted); margin-top: 5px; }

.result-actions { display: flex; flex-wrap: wrap; gap: 10px; margin: 16px 0; }
.result-actions .btn { flex: 1; min-width: 130px; }

.answer-legend { display: flex; flex-wrap: wrap; gap: 8px 16px; font-size: 12.5px; color: var(--text-muted); margin-bottom: 12px; }
.answer-legend span { display: flex; align-items: center; gap: 5px; }
.answer-legend i { width: 11px; height: 11px; border-radius: 3px; border: 1.5px solid; }
.answer-legend .c i { background: var(--success-soft); border-color: var(--success); }
.answer-legend .w i { background: var(--danger-soft); border-color: var(--danger); }
.answer-legend .m i { background: var(--success-soft); border-color: var(--success); border-style: dashed; }

.filter-bar { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 14px; }
.chip {
  padding: 6px 13px;
  border-radius: 999px;
  border: 1.5px solid var(--border);
  background: var(--surface);
  color: var(--text-soft);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
}
.chip.is-active { background: var(--primary); border-color: var(--primary); color: #fff; }

.empty { text-align: center; padding: 46px 20px; color: var(--text-muted); }
.empty__title { font-size: 16px; color: var(--text-soft); font-weight: 600; margin-bottom: 6px; }

/* ------------------------------- 记录页 ------------------------------- */

.records-table td { vertical-align: middle; }
.records-table .name { font-weight: 600; }
.tag {
  display: inline-block;
  padding: 2px 9px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
}
.tag--pass { background: var(--success-soft); color: var(--success); }
.tag--fail { background: var(--danger-soft); color: var(--danger); }

.score-pill { font-weight: 800; font-variant-numeric: tabular-nums; }
.score-pill.is-pass { color: var(--success); }
.score-pill.is-fail { color: var(--danger); }

@media (max-width: 720px) {
  .records-table thead { display: none; }
  .records-table tr {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 4px 10px;
    padding: 12px 2px;
    border-bottom: 1px solid var(--border);
  }
  .records-table td { border: none; padding: 2px 0; display: flex; justify-content: space-between; gap: 12px; }
  .records-table td::before {
    content: attr(data-label);
    color: var(--text-muted);
    font-size: 13px;
    flex: none;
  }
  .records-table td[data-label="姓名"] { font-size: 15px; }
  .records-table td[data-label="姓名"]::before { display: none; }
  .records-table td.span-2 { grid-column: 1 / -1; }
}

/* ------------------------------- 提示 / 弹窗 ------------------------------- */

.toast-host {
  position: fixed;
  left: 50%;
  bottom: 26px;
  transform: translateX(-50%);
  z-index: 90;
  display: grid;
  gap: 8px;
  pointer-events: none;
  width: max-content;
  max-width: min(92vw, 420px);
}
.toast {
  padding: 10px 16px;
  border-radius: 999px;
  background: rgba(15, 23, 42, .93);
  color: #fff;
  font-size: 14px;
  box-shadow: 0 8px 24px rgba(15, 23, 42, .28);
  animation: toast-in .22s ease;
}
.toast--error { background: var(--danger); }
.toast--success { background: var(--success); }

@keyframes toast-in { from { opacity: 0; transform: translateY(10px); } }

.modal-host {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: grid;
  place-items: center;
  padding: 20px;
  background: rgba(15, 23, 42, .5);
  backdrop-filter: blur(2px);
}

.modal {
  width: min(420px, 100%);
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 20px;
  animation: toast-in .2s ease;
}
.modal__title { font-size: 17px; margin-bottom: 8px; }
.modal__body { font-size: 14px; color: var(--text-soft); }
.modal__list { list-style: none; margin: 12px 0; padding: 0; display: grid; gap: 6px; font-size: 13.5px; }
.modal__list li { display: flex; justify-content: space-between; gap: 12px; padding: 7px 11px; border-radius: var(--radius-sm); background: var(--surface-2); }
.modal__list b { font-variant-numeric: tabular-nums; }
.modal__actions { display: flex; gap: 10px; margin-top: 16px; }
.modal__actions .btn { flex: 1; }

/* ------------------------------- 桌面端 ------------------------------- */

@media (min-width: 1000px) {
  :root { --topbar-h: 60px; }

  #main { padding: 24px 16px 48px; }

  .hero { padding: 14px 4px 24px; }
  .hero__title { font-size: 32px; }
  .hero__sub { font-size: 15px; }

  .stat-grid { grid-template-columns: repeat(4, 1fr); }

  .exam-bar { margin: -24px -16px 16px; padding: 12px 18px; }
  .exam-bar__actions { display: flex; }

  .exam-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 268px;
    gap: 20px;
    align-items: start;
  }

  .palette {
    position: sticky;
    top: calc(var(--topbar-h) + 66px);
    left: auto;
    right: auto;
    bottom: auto;
    max-height: calc(100vh - var(--topbar-h) - 86px);
    transform: none;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 15px;
    box-shadow: var(--shadow-sm);
  }
  .palette__close { display: none; }
  .palette__grid { grid-template-columns: repeat(5, 1fr); }

  .exam-footbar { display: none; }

  .q-card { padding: 19px 20px; }
  .q-stem { font-size: 15.5px; }
  .q-option__text { font-size: 15px; }

  .modal__actions { justify-content: flex-end; }
  .modal__actions .btn { flex: 0 0 auto; min-width: 96px; }

  body[data-view="exam"] #main { padding-bottom: 48px; }
}

/* ------------------------------- 页面状态微调 ------------------------------- */

/* 答题时不显示顶部导航（防止误触离开），并给底部操作条留出空间 */
body[data-view="exam"] .topnav { display: none; }
body[data-view="exam"] #main { padding-bottom: 96px; }
body[data-view="home"] .topnav a[data-nav="home"],
body[data-view="records"] .topnav a[data-nav="records"] { }

/* 窄屏顶栏：省掉副标题、收紧间距，保证三个入口一行放得下且不换行 */
@media (max-width: 640px) {
  .topbar__inner { padding: 0 12px; gap: 8px; }
  .brand { gap: 7px; }
  .brand__mark { width: 27px; height: 27px; font-size: 14px; border-radius: 8px; }
  .brand__text strong { font-size: 14px; }
  .brand__text small { display: none; }
  .topnav { gap: 2px; }
  .topnav a { padding: 6px 8px; font-size: 13.5px; }
}

/* 再窄一点（320~360px 的老设备）只留品牌名，导航靠图标化后的短文字 */
@media (max-width: 400px) {
  .brand__text { display: none; }
  .topnav a { padding: 6px 7px; font-size: 13px; }
}

/* ------------------------------- 管理后台 ------------------------------- */

.card--admin-login { max-width: 420px; margin: 24px auto; }
.admin-login-form { display: grid; gap: 12px; }

.admin-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 16px;
  margin-bottom: 16px;
}
.admin-header__title { font-size: 22px; }
.admin-header__sub { margin: 2px 0 0; font-size: 13.5px; color: var(--text-muted); }
.admin-header > .btn { margin-left: auto; }

.admin-tabs {
  display: flex;
  gap: 6px;
  margin-bottom: 16px;
  overflow-x: auto;
  padding-bottom: 2px;
}
.admin-tab {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 9px 15px;
  border-radius: 999px;
  border: 1.5px solid var(--border);
  background: var(--surface);
  color: var(--text-soft);
  font: inherit;
  font-size: 14.5px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}
.admin-tab:hover { border-color: var(--primary); color: var(--primary-strong); }
.admin-tab.is-active { background: var(--primary); border-color: var(--primary); color: #fff; }
.admin-tab__badge {
  min-width: 20px;
  padding: 0 6px;
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--text-muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}
.admin-tab.is-active .admin-tab__badge { background: rgba(255, 255, 255, .24); color: #fff; }

.admin-toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 12px; }
.admin-toolbar__spacer { flex: 1; }
.admin-toolbar__meta { font-size: 12.5px; color: var(--text-muted); }

.btn--danger { color: var(--danger); border-color: color-mix(in srgb, var(--danger) 45%, transparent); }
.btn--danger:hover { background: var(--danger-soft); border-color: var(--danger); color: var(--danger); }

.admin-counts { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-bottom: 16px; }
.count-chip { background: var(--surface-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 11px 13px; }
.count-chip.is-short { border-color: var(--danger); background: var(--danger-soft); }
.count-chip__value { font-size: 21px; font-weight: 800; font-variant-numeric: tabular-nums; line-height: 1.2; }
.count-chip.is-short .count-chip__value { color: var(--danger); }
.count-chip__label { font-size: 13px; color: var(--text-soft); }
.count-chip__need { font-size: 11.5px; color: var(--text-muted); }

.alert {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 11px 14px;
  border-radius: var(--radius);
  margin-bottom: 14px;
  font-size: 14px;
}
.alert--warn { background: var(--warning-soft); color: var(--warning); border: 1px solid color-mix(in srgb, var(--warning) 40%, transparent); }

.bank-list { display: grid; gap: 10px; }
.bank-item { border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 14px; background: var(--surface); }
.bank-item__head { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.bank-item__answer { font-size: 13px; font-weight: 700; color: var(--success); }
.bank-item__stem { margin-top: 7px; font-size: 14px; line-height: 1.6; color: var(--text-soft); }

.editor { border-color: var(--primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 12%, transparent); }
.editor__grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 12px; }
.editor .field { margin-bottom: 12px; }
.editor__actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: 14px; }
.edit-options { display: grid; gap: 8px; }
.edit-option { display: flex; align-items: center; gap: 8px; }
.edit-option__key { flex: none; width: 30px; text-align: center; font-size: 13px; font-weight: 700; color: var(--text-muted); }
.edit-answer-picker { display: flex; gap: 8px; }

.field__textarea { resize: vertical; line-height: 1.6; min-height: 44px; }
.field__help { display: block; margin-top: 6px; font-size: 12.5px; color: var(--text-muted); font-weight: 400; }

.switch { display: flex; align-items: center; gap: 11px; cursor: pointer; }
.switch input { position: absolute; opacity: 0; width: 0; height: 0; }
.switch__track { flex: none; width: 44px; height: 25px; border-radius: 999px; background: var(--border-strong); position: relative; transition: background .18s; }
.switch__track::after {
  content: '';
  position: absolute;
  top: 3px;
  left: 3px;
  width: 19px;
  height: 19px;
  border-radius: 50%;
  background: #fff;
  transition: transform .18s;
  box-shadow: 0 1px 3px rgba(0, 0, 0, .3);
}
.switch input:checked + .switch__track { background: var(--primary); }
.switch input:checked + .switch__track::after { transform: translateX(19px); }
.switch input:focus-visible + .switch__track { outline: 3px solid color-mix(in srgb, var(--primary) 40%, transparent); outline-offset: 2px; }
.switch__label { font-size: 14.5px; font-weight: 600; }

.wl-add { margin-bottom: 16px; }
.wl-chips { display: flex; flex-wrap: wrap; gap: 8px; }
.wl-chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 6px 6px 13px;
  border-radius: 999px;
  background: var(--primary-soft);
  border: 1px solid color-mix(in srgb, var(--primary) 35%, transparent);
  color: var(--primary-strong);
  font-size: 14px;
  font-weight: 600;
}
.wl-chip__x {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: none;
  background: color-mix(in srgb, var(--primary) 20%, transparent);
  color: inherit;
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
}
.wl-chip__x:hover { background: var(--danger); color: #fff; }

.code-block {
  display: block;
  margin-top: 12px;
  padding: 11px 13px;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  border: 1px solid var(--border);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
  color: var(--text);
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-all;
}

.notice-box {
  padding: 12px 15px;
  margin-bottom: 16px;
  border-radius: var(--radius);
  background: var(--primary-soft);
  border: 1px solid color-mix(in srgb, var(--primary) 28%, transparent);
  color: var(--text-soft);
  font-size: 14px;
  line-height: 1.65;
}
.notice-box--lock { background: var(--warning-soft); border-color: color-mix(in srgb, var(--warning) 40%, transparent); }

.name.anon { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; letter-spacing: .06em; }

@media (max-width: 640px) {
  .editor__grid { grid-template-columns: 1fr; }
  .admin-counts { grid-template-columns: 1fr; }
}

/* ------------------------------- 打印 ------------------------------- */

@media print {
  .topbar, .exam-bar, .exam-footbar, .palette, .result-actions, .toast-host { display: none !important; }
  body { background: #fff; }
  .q-card { break-inside: avoid; box-shadow: none; }
}