/* Extracted from the original single-file page; app structure is now modular. */
:root {
  --bg: #f6f8fb;
  --card: #ffffff;
  --text: #14213d;
  --muted: #64748b;
  --line: #dbe3ef;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --green-bg: #dcfce7;
  --green-border: #16a34a;
  --green-text: #14532d;
  --red-bg: #fee2e2;
  --red-border: #dc2626;
  --red-text: #7f1d1d;
  --yellow-bg: #fef9c3;
  --yellow-border: #ca8a04;
  --yellow-text: #713f12;
  --answer-bg: #eff6ff;
  --answer-border: #60a5fa;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, #edf4ff 0, var(--bg) 260px);
}
header {
  padding: 28px 22px 18px;
  max-width: 1180px;
  margin: 0 auto;
}
h1 { margin: 0 0 10px; font-size: 28px; letter-spacing: .5px; }
.subtitle { color: var(--muted); font-size: 14px; line-height: 1.8; }
.toolbar {
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  box-shadow: 0 4px 18px rgba(15, 23, 42, .05);
}
.toolbar-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 12px 22px;
}
.controls { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
button, select, input[type="search"] {
  font: inherit;
}
.btn {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  border-radius: 10px;
  padding: 9px 12px;
  cursor: pointer;
  transition: .15s ease;
}
.btn:hover { border-color: var(--primary); color: var(--primary-dark); }
.btn.primary {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}
.btn.primary:hover { background: var(--primary-dark); color: #fff; }
.search {
  min-width: 260px;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 12px;
}
.select {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 12px;
  background: #fff;
}
.stats {
  color: var(--muted);
  font-size: 13px;
  text-align: right;
  line-height: 1.7;
}
main { max-width: 1180px; margin: 18px auto 60px; padding: 0 22px; }
.q-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px;
  margin: 14px 0;
  box-shadow: 0 8px 26px rgba(15, 23, 42, .045);
}
.q-card.hidden { display: none; }
.q-head { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-bottom: 10px; }
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  border-radius: 999px;
  padding: 4px 9px;
  background: #eef2ff;
  color: #3730a3;
  border: 1px solid #c7d2fe;
}
.badge.type-多选题 { background: #fef3c7; color: #92400e; border-color: #fde68a; }
.badge.type-判断题 { background: #ecfdf5; color: #065f46; border-color: #a7f3d0; }
.stem { font-size: 16px; line-height: 1.8; margin: 8px 0 12px; white-space: pre-wrap; }
.options { display: grid; grid-template-columns: 1fr; gap: 8px; }
.option {
  display: grid;
  grid-template-columns: 38px 1fr;
  gap: 10px;
  align-items: start;
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  padding: 10px 12px;
  text-align: left;
  cursor: pointer;
  line-height: 1.65;
}
.option:hover { border-color: #94a3b8; background: #f8fafc; }
.key {
  display: inline-flex;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  align-items: center;
  justify-content: center;
  background: #f1f5f9;
  color: #334155;
  font-weight: 700;
}
.option.selected { border-color: var(--primary); background: #eff6ff; }
.option.correct { border-color: var(--green-border); background: var(--green-bg); color: var(--green-text); }
.option.correct .key { background: var(--green-border); color: #fff; }
.option.wrong { border-color: var(--red-border); background: var(--red-bg); color: var(--red-text); }
.option.wrong .key { background: var(--red-border); color: #fff; }
.option.answer-highlight { border-color: var(--green-border); background: var(--green-bg); color: var(--green-text); }
.option.answer-highlight .key { background: var(--green-border); color: #fff; }
.option.partial { border-color: var(--yellow-border); background: var(--yellow-bg); color: var(--yellow-text); }
.option.partial .key { background: var(--yellow-border); color: #fff; }
.feedback { margin-top: 10px; min-height: 24px; font-size: 14px; font-weight: 700; }
.feedback.ok { color: var(--green-text); }
.feedback.bad { color: var(--red-text); }
.feedback.wait { color: var(--yellow-text); }
.answer-line {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 12px;
  background: #f8fafc;
  border: 1px dashed #94a3b8;
  color: #334155;
  line-height: 1.7;
}
.meta { margin-top: 10px; color: var(--muted); font-size: 13px; line-height: 1.8; }
.small-actions { margin-top: 10px; display: flex; gap: 8px; flex-wrap: wrap; }
.mini { padding: 5px 9px; border-radius: 8px; font-size: 12px; }
#backTop {
  position: fixed;
  right: 22px;
  bottom: 22px;
  border-radius: 999px;
  width: 46px;
  height: 46px;
  border: 1px solid var(--line);
  background: #fff;
  box-shadow: 0 8px 24px rgba(15,23,42,.18);
  cursor: pointer;
}
@media (min-width: 780px) {
  .options { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 760px) {
  .toolbar-inner { grid-template-columns: 1fr; }
  .stats { text-align: left; }
  .search { min-width: 100%; }
  h1 { font-size: 22px; }
}
/* 手机端滚动时自动隐藏顶部工具栏：向下滚动隐藏，向上滚动或回到顶部显示 */
@media (max-width: 760px) {
  .toolbar {
    transition: transform .24s ease, box-shadow .24s ease;
    will-change: transform;
  }
  .toolbar.mobile-hidden {
    transform: translateY(calc(-100% - 4px));
    box-shadow: none;
  }
}
@media (prefers-reduced-motion: reduce) {
  .toolbar { transition: none; }
}
@media print {
  .toolbar, #backTop { display:none !important; }
  body { background:#fff; }
  .q-card { page-break-inside: avoid; box-shadow:none; }
}

.hidden { display: none !important; }
.bank-screen {
  max-width: 1180px;
  margin: 0 auto;
  padding: 38px 22px 70px;
}
.bank-title { margin: 0 0 10px; font-size: 30px; }
.bank-subtitle { color: var(--muted); line-height: 1.8; margin-bottom: 22px; }
.bank-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 14px; }
.bank-card {
  border: 1px solid var(--line);
  background: var(--card);
  border-radius: 8px;
  padding: 18px;
  text-align: left;
  box-shadow: 0 8px 24px rgba(15,23,42,.06);
  cursor: pointer;
}
.bank-card:hover { border-color: var(--primary); box-shadow: 0 12px 30px rgba(37,99,235,.12); }
.bank-card h2 { margin: 0 0 10px; font-size: 19px; line-height: 1.45; }
.bank-card p { margin: 0; color: var(--muted); line-height: 1.7; }
.app-shell { min-height: 100vh; }
.code-block, .answer-code {
  white-space: pre-wrap;
  overflow-x: auto;
  background: #0f172a;
  color: #e2e8f0;
  border-radius: 8px;
  padding: 16px;
  line-height: 1.65;
  font-size: 13px;
  font-family: Consolas, "SFMono-Regular", Menlo, Monaco, monospace;
}
.answer-code { background: #ecfdf5; color: #064e3b; border: 1px solid var(--green-border); }
.practice-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 12px; }
.practice-answer { margin-top: 12px; }
.practice-answer-title { font-weight: 700; color: var(--green-text); margin: 0 0 8px; }