/* 实习技能学习中心 · 样式 */
:root {
  --bg: #f6f7f9;
  --panel: #ffffff;
  --ink: #1f2937;
  --ink-2: #6b7280;
  --line: #e5e7eb;
  --brand: #1d4ed8;
  --brand-soft: #eef2ff;
  --ok: #059669;
  --ok-soft: #ecfdf5;
  --bad: #dc2626;
  --bad-soft: #fef2f2;
  --radius: 12px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.8;
  font-size: 15.5px;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

/* 顶栏 */
.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 10px 22px;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 12px; min-width: 0; }
.logo { font-size: 26px; }
.brand h1 { margin: 0; font-size: 17px; white-space: nowrap; }
.brand .sub { margin: 0; color: var(--ink-2); font-size: 12.5px; white-space: nowrap; }
.search-wrap input {
  width: 340px; max-width: 42vw;
  padding: 9px 14px; border: 1px solid var(--line); border-radius: 999px;
  font-size: 14px; outline: none; background: #fff; color: var(--ink);
}
.search-wrap input:focus { border-color: var(--brand); box-shadow: 0 0 0 3px var(--brand-soft); }

/* 布局 */
.layout {
  display: grid; grid-template-columns: 300px minmax(0, 1fr);
  gap: 22px; max-width: 1280px; margin: 22px auto; padding: 0 22px;
}
.sidebar {
  position: sticky; top: 76px; align-self: start;
  max-height: calc(100vh - 104px); overflow: auto;
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 10px;
}
.main { min-width: 0; }

/* 侧边导航 */
.nav-home {
  display: flex; align-items: center; gap: 8px;
  padding: 9px 12px; border-radius: 9px;
  color: var(--ink); font-weight: 600; font-size: 14.5px;
}
.nav-home:hover { background: var(--brand-soft); text-decoration: none; }
.nav-home.active { background: var(--brand-soft); color: var(--brand); }
.nav-group { margin-top: 10px; }
.nav-title {
  padding: 6px 12px 4px; font-size: 12.5px; color: var(--ink-2);
  letter-spacing: .04em; border-top: 1px dashed var(--line); margin-top: 8px;
}
.nav-item {
  display: flex; gap: 8px; align-items: baseline;
  padding: 7px 12px; border-radius: 9px;
  color: var(--ink); font-size: 14px; line-height: 1.5;
}
.nav-item:hover { background: #f3f4f6; text-decoration: none; }
.nav-item.active { background: var(--brand-soft); color: var(--brand); font-weight: 600; }
.nav-item .dot { color: var(--ink-2); font-size: 12px; }
.nav-item.done .dot { color: var(--ok); font-weight: 700; }
.nav-note { padding: 8px 12px; font-size: 12.5px; color: var(--ink-2); }
.pill {
  display: inline-block; margin-left: 6px; padding: 0 8px;
  background: var(--bad-soft); color: var(--bad);
  border-radius: 999px; font-size: 12px; font-weight: 700;
}

/* 卡片与首页 */
.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px 22px; margin-bottom: 18px;
}
.hero h2 { margin: 0 0 8px; font-size: 21px; }
.hero p { margin: 6px 0; }
.muted { color: var(--ink-2); font-size: 13px; }
.stats { display: flex; gap: 14px; flex-wrap: wrap; margin: 14px 0 6px; }
.stat {
  flex: 1; min-width: 130px; text-align: center;
  background: var(--brand-soft); border-radius: 10px; padding: 12px 8px;
}
.stat .num { font-size: 21px; font-weight: 700; color: var(--brand); }
.stat .lab { font-size: 12.5px; color: var(--ink-2); }

.module-card .module-head { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.module-card h3 { margin: 0; font-size: 17px; }
.bar { height: 8px; background: #eef0f3; border-radius: 999px; margin: 12px 0 10px; overflow: hidden; }
.bar-in { height: 100%; background: linear-gradient(90deg, #3b82f6, #1d4ed8); border-radius: 999px; transition: width .3s; }
.module-meta { display: flex; justify-content: space-between; align-items: center; color: var(--ink-2); font-size: 13.5px; }
.lesson-list { margin: 12px 0 0; padding-left: 22px; color: var(--ink); }
.lesson-list li { margin: 4px 0; }
.tip-card ul { margin: 8px 0 0; padding-left: 20px; }

/* 课程正文 */
.crumb { color: var(--ink-2); font-size: 13px; margin-bottom: 6px; }
.lesson-title { margin: 0 0 14px; font-size: 22px; line-height: 1.4; }
.md {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 8px 26px 18px;
}
.md h3 { font-size: 16.5px; margin: 18px 0 6px; color: var(--brand); }
.md ul, .md ol { padding-left: 22px; margin: 6px 0; }
.md li { margin: 3px 0; }
.md p { margin: 8px 0; }
.md strong { color: #111827; }
.md blockquote {
  margin: 10px 0; padding: 6px 14px; border-left: 3px solid var(--brand);
  background: var(--brand-soft); border-radius: 0 8px 8px 0; color: #374151;
}
.md code { background: #f3f4f6; border-radius: 6px; padding: 1px 6px; font-size: 13.5px; }
.lesson-actions { display: flex; gap: 12px; margin: 16px 0 4px; flex-wrap: wrap; }

/* 按钮 */
.btn {
  display: inline-block; border: 1px solid transparent; cursor: pointer;
  border-radius: 9px; padding: 9px 16px; font-size: 14.5px;
  font-family: inherit; line-height: 1.4;
}
.btn:hover { text-decoration: none; filter: brightness(.97); }
.btn-primary { background: var(--brand); color: #fff; }
.btn-ok { background: var(--ok-soft); color: var(--ok); border-color: #a7f3d0; }
.btn-ghost { background: #fff; color: var(--ink); border-color: var(--line); }
.btn-sm { padding: 6px 12px; font-size: 13.5px; }

/* 自测题 */
.quiz-h { font-size: 17px; margin: 26px 0 12px; }
.q {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 14px 20px 16px; margin-bottom: 14px;
}
.q-text { margin: 0 0 10px; font-weight: 600; }
.opts { display: flex; flex-direction: column; gap: 8px; }
.opt {
  text-align: left; border: 1px solid var(--line); background: #fff;
  border-radius: 9px; padding: 9px 14px; font-size: 14.5px; cursor: pointer;
  font-family: inherit; color: var(--ink); line-height: 1.6;
}
.opt:hover:not(:disabled) { border-color: var(--brand); background: var(--brand-soft); }
.opt:disabled { cursor: default; opacity: .92; }
.opt.correct { border-color: #34d399; background: var(--ok-soft); color: #065f46; font-weight: 600; }
.opt.wrong { border-color: #f87171; background: var(--bad-soft); color: #991b1b; }
.explain {
  margin-top: 12px; padding: 10px 14px; border-radius: 9px;
  background: #f9fafb; border: 1px dashed var(--line);
  font-size: 14px; color: #374151;
}

/* 错题本 */
.wrong-card .wrong-src { margin: 0 0 8px; color: var(--ink-2); font-size: 13px; }
.w-opt {
  padding: 5px 4px; font-size: 14.5px; color: #4b5563;
}
.w-opt.w-ok { color: var(--ok); font-weight: 600; }
.w-opt.w-bad { color: var(--bad); }
.wrong-card .explain { margin-bottom: 12px; }

/* 上一课/下一课 */
.pager {
  display: flex; justify-content: space-between; gap: 14px;
  margin: 26px 0 10px; flex-wrap: wrap;
}
.pager-link {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 10px; padding: 10px 16px; font-size: 14px;
  max-width: 46%;
}
.done-tip { color: var(--ok); border-style: dashed; }

.footer {
  text-align: center; color: var(--ink-2);
  font-size: 12.5px; padding: 26px 16px 34px;
}

/* 窄屏 */
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; gap: 14px; padding: 0 12px; margin: 14px auto; }
  .sidebar { position: static; max-height: none; }
  .search-wrap input { width: 160px; }
  .brand .sub { display: none; }
  .md { padding: 4px 16px 14px; }
}