/* ============================================================
   生物医学科研入门网站 · 全站样式
   配色：医学青绿 + 墨蓝 + 珊瑚点缀
   ============================================================ */

:root {
  --teal-700: #0a5d56;
  --teal-600: #0d7a72;
  --teal-500: #12948a;
  --teal-100: #dcf0ed;
  --teal-50:  #f0f9f8;
  --indigo-600: #3b5bdb;
  --indigo-50: #eef2fd;
  --amber-600: #b45309;
  --amber-50:  #fef3e2;
  --red-600:   #c23325;
  --red-50:    #fdeeed;
  --green-700: #15803d;
  --green-50:  #ecf7ef;

  --ink-900: #16232b;
  --ink-700: #2c3e49;
  --ink-500: #5b6b76;
  --ink-300: #9aa8b0;

  --bg:   #f6faf9;
  --card: #ffffff;
  --line: #e2ecea;

  --radius: 12px;
  --shadow-sm: 0 1px 3px rgba(22, 35, 43, .07);
  --shadow-md: 0 8px 24px rgba(22, 35, 43, .10);
  --font: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", "Segoe UI", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink-900);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--teal-600); text-decoration: none; }
a:hover { text-decoration: underline; }

img, svg { max-width: 100%; }

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }

/* ---------------- 顶部导航 ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex; align-items: center; gap: 28px;
  max-width: 1100px; margin: 0 auto; padding: 0 20px;
  height: 60px;
}
.logo {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: 17px; color: var(--ink-900);
  white-space: nowrap;
}
.logo:hover { text-decoration: none; }
.logo svg { width: 26px; height: 26px; flex: none; }
.logo .sub { font-size: 12px; font-weight: 400; color: var(--ink-500); display: block; line-height: 1.1; }
.nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav a {
  padding: 6px 12px; border-radius: 8px;
  color: var(--ink-700); font-size: 15px;
}
.nav a:hover { background: var(--teal-50); text-decoration: none; color: var(--teal-700); }
.nav a.active { background: var(--teal-600); color: #fff; }
.nav a.nav-search { display: flex; align-items: center; gap: 4px; }
.nav .nav-short { display: none; }

/* ---------------- 首页 Hero ---------------- */
.hero {
  background: linear-gradient(135deg, var(--teal-700) 0%, var(--teal-600) 55%, var(--teal-500) 100%);
  color: #fff; padding: 64px 0 72px;
  position: relative; overflow: hidden;
}
.hero::after {
  content: ""; position: absolute; right: -80px; top: -80px;
  width: 340px; height: 340px; border-radius: 50%;
  background: rgba(255, 255, 255, .08);
}
.hero::before {
  content: ""; position: absolute; right: 120px; bottom: -120px;
  width: 240px; height: 240px; border-radius: 50%;
  background: rgba(255, 255, 255, .06);
}
.hero h1 { font-size: 34px; line-height: 1.35; margin-bottom: 14px; position: relative; z-index: 1; }
.hero p { font-size: 17px; opacity: .92; max-width: 640px; position: relative; z-index: 1; }
.hero-btns { display: flex; gap: 14px; margin-top: 28px; flex-wrap: wrap; position: relative; z-index: 1; }
.btn {
  display: inline-block; padding: 10px 22px; border-radius: 10px;
  font-size: 15px; font-weight: 600; border: 1px solid transparent;
  transition: all .15s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-light { background: #fff; color: var(--teal-700); }
.btn-light:hover { background: var(--teal-50); }
.btn-outline { border-color: rgba(255,255,255,.6); color: #fff; }
.btn-outline:hover { background: rgba(255,255,255,.12); }
.btn-primary { background: var(--teal-600); color: #fff; }
.btn-primary:hover { background: var(--teal-700); }

/* ---------------- 通用板块 ---------------- */
.section { padding: 52px 0; }
.section-title {
  display: flex; align-items: baseline; gap: 12px;
  font-size: 24px; margin-bottom: 6px;
}
.section-title::before {
  content: ""; width: 5px; height: 22px; border-radius: 3px;
  background: var(--teal-600); align-self: center;
}
.section-desc { color: var(--ink-500); margin-bottom: 26px; font-size: 15px; }

/* ---------------- 卡片 ---------------- */
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 18px; }
.card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 22px;
  box-shadow: var(--shadow-sm);
  transition: all .18s;
  display: flex; flex-direction: column; gap: 10px;
}
.card:hover {
  box-shadow: var(--shadow-md); transform: translateY(-3px);
  border-color: var(--teal-100); text-decoration: none;
}
.card-top { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.card h3 { font-size: 17.5px; line-height: 1.5; }
.card h3 a { color: var(--ink-900); }
.card p { color: var(--ink-500); font-size: 14.5px; flex: 1; }
.card .card-foot { display: flex; justify-content: space-between; align-items: center; font-size: 12.5px; color: var(--ink-300); }

.badge {
  display: inline-block; padding: 2px 10px; border-radius: 999px;
  font-size: 12px; font-weight: 600; line-height: 1.7; white-space: nowrap;
}
.badge-start  { background: var(--green-50); color: var(--green-700); }
.badge-adv    { background: var(--indigo-50); color: var(--indigo-600); }
.badge-lit    { background: var(--indigo-50); color: var(--indigo-600); }
.badge-tech   { background: var(--teal-100); color: var(--teal-700); }
.badge-proj   { background: var(--amber-50); color: var(--amber-600); }
.tag {
  display: inline-block; padding: 1px 9px; border-radius: 6px;
  background: var(--teal-50); color: var(--teal-700);
  font-size: 12.5px;
}
a.tag:hover { background: var(--teal-100); text-decoration: none; }

/* ---------------- 板块页 ---------------- */
.page-head { padding: 44px 0 8px; }
.page-head h1 { font-size: 28px; display: flex; align-items: center; gap: 12px; }
.page-head .crumb { font-size: 13.5px; color: var(--ink-300); margin-bottom: 8px; }
.page-head .crumb a { color: var(--ink-500); }
.page-head p { color: var(--ink-500); margin-top: 8px; max-width: 720px; }

.filter-bar { display: flex; flex-wrap: wrap; gap: 8px; margin: 22px 0 6px; align-items: center; }
.chip {
  border: 1px solid var(--line); background: #fff; color: var(--ink-700);
  padding: 4px 14px; border-radius: 999px; font-size: 13.5px; cursor: pointer;
  transition: all .15s; font-family: var(--font);
}
.chip:hover { border-color: var(--teal-500); color: var(--teal-600); }
.chip.active { background: var(--teal-600); border-color: var(--teal-600); color: #fff; }

.list-count { font-size: 13px; color: var(--ink-300); margin-left: 6px; }

/* ---------------- 文章页 ---------------- */
.article-layout {
  display: grid; grid-template-columns: 230px minmax(0, 1fr);
  gap: 40px; max-width: 1100px; margin: 0 auto; padding: 36px 20px 64px;
}
.toc { position: sticky; top: 84px; align-self: start; max-height: calc(100vh - 110px); overflow-y: auto; }
.toc-title { font-size: 13px; font-weight: 700; color: var(--ink-300); letter-spacing: 1px; margin-bottom: 10px; }
.toc a {
  display: block; padding: 5px 0 5px 12px; border-left: 2px solid var(--line);
  font-size: 13.5px; color: var(--ink-500); line-height: 1.55;
}
.toc a:hover { color: var(--teal-600); text-decoration: none; }
.toc a.lv3 { padding-left: 26px; font-size: 13px; }
.toc a.active { border-left-color: var(--teal-600); color: var(--teal-700); font-weight: 600; }

.article {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 40px 48px; box-shadow: var(--shadow-sm);
  max-width: 860px; width: 100%;
}
.article > h1 { font-size: 27px; line-height: 1.5; margin-bottom: 10px; }
.article .meta-row {
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
  padding-bottom: 20px; margin-bottom: 26px; border-bottom: 1px solid var(--line);
  font-size: 13px; color: var(--ink-300);
}

/* 文章正文排版 */
.article h2 {
  font-size: 21px; margin: 42px 0 14px; padding-left: 12px;
  border-left: 4px solid var(--teal-600); line-height: 1.5;
}
.article h3 { font-size: 17.5px; margin: 28px 0 10px; color: var(--ink-900); }
.article p { margin: 12px 0; font-size: 16.5px; }
.article ul, .article ol { padding-left: 26px; margin: 12px 0; }
.article li { margin: 6px 0; font-size: 16.5px; }
.article strong { color: var(--teal-700); }
.article code, .inline-code {
  background: var(--teal-50); color: var(--teal-700);
  padding: 1px 7px; border-radius: 5px; font-size: 14.5px;
  font-family: Consolas, "Courier New", monospace;
}
.article pre {
  background: var(--ink-900); color: #dce9f2; border-radius: 10px;
  padding: 16px 20px; overflow-x: auto; margin: 14px 0;
  font-size: 14px; line-height: 1.8; font-family: Consolas, "Courier New", monospace;
}
.article pre code { background: none; color: inherit; padding: 0; }
.article table {
  width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 14.5px;
  display: block; overflow-x: auto;
}
.article th {
  background: var(--teal-50); color: var(--teal-700);
  text-align: left; padding: 9px 14px; font-weight: 600; white-space: nowrap;
}
.article td { padding: 9px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
.article tr:last-child td { border-bottom: 2px solid var(--teal-100); }
.article blockquote {
  border-left: 4px solid var(--teal-500); background: var(--teal-50);
  padding: 12px 20px; border-radius: 0 10px 10px 0; margin: 14px 0;
  color: var(--ink-700);
}

/* 提示框系列 */
.callout {
  border-radius: 10px; padding: 16px 20px; margin: 18px 0;
  font-size: 15.5px; line-height: 1.8;
}
.callout .callout-title { font-weight: 700; margin-bottom: 4px; display: flex; align-items: center; gap: 7px; }
.callout p { margin: 4px 0; font-size: 15.5px; }
.callout ul, .callout ol { margin: 4px 0; }
.callout li { font-size: 15.5px; }
.callout-tip    { background: var(--green-50); border: 1px solid #bfe3cb; }
.callout-tip .callout-title { color: var(--green-700); }
.callout-warn   { background: var(--amber-50); border: 1px solid #f3d9ae; }
.callout-warn .callout-title { color: var(--amber-600); }
.callout-danger { background: var(--red-50); border: 1px solid #f2c5c0; }
.callout-danger .callout-title { color: var(--red-600); }
.callout-info   { background: var(--indigo-50); border: 1px solid #ccd8f7; }
.callout-info .callout-title { color: var(--indigo-600); }
.callout-group  { background: repeating-linear-gradient(-45deg, #fdf9f2, #fdf9f2 12px, #faf3e6 12px, #faf3e6 24px); border: 1.5px dashed #d9b98a; }
.callout-group .callout-title { color: #9a6b1f; }

/* 图示 */
.figure { margin: 22px 0; text-align: center; }
.figure svg { max-width: 100%; height: auto; }
.figure svg text { font-family: var(--font); }
.figure .fig-caption {
  font-size: 13.5px; color: var(--ink-500); margin-top: 10px;
}
.figure .fig-caption b { color: var(--teal-700); }

/* 步骤流程 */
.step-list { counter-reset: step; margin: 18px 0; }
.step-item {
  position: relative; padding: 14px 16px 14px 58px;
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  margin-bottom: 10px;
}
.step-item::before {
  counter-increment: step; content: counter(step);
  position: absolute; left: 14px; top: 14px;
  width: 30px; height: 30px; border-radius: 50%;
  background: var(--teal-600); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 15px;
}
.step-item b { display: block; margin-bottom: 2px; }
.step-item p, .step-item span { font-size: 15px; color: var(--ink-700); margin: 2px 0; }

/* 上一篇/下一篇 */
.article-nav { display: flex; gap: 12px; margin-top: 34px; padding-top: 22px; border-top: 1px solid var(--line); }
.article-nav a {
  flex: 1; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px 16px; font-size: 14px; color: var(--ink-700); background: #fff;
}
.article-nav a:hover { border-color: var(--teal-500); text-decoration: none; color: var(--teal-700); }
.article-nav a .nav-label { display: block; font-size: 12px; color: var(--ink-300); margin-bottom: 3px; }

/* ---------------- 学习路线（首页） ---------------- */
.roadmap { position: relative; margin-top: 8px; }
.roadmap::before {
  content: ""; position: absolute; left: 19px; top: 8px; bottom: 8px;
  width: 2px; background: var(--teal-100);
}
.road-item { position: relative; padding: 0 0 26px 58px; }
.road-item::before {
  content: ""; position: absolute; left: 12px; top: 6px;
  width: 16px; height: 16px; border-radius: 50%;
  background: #fff; border: 4px solid var(--teal-600);
}
.road-item .road-when { font-size: 13px; font-weight: 700; color: var(--teal-600); letter-spacing: .5px; }
.road-item h4 { font-size: 16.5px; margin: 2px 0 4px; }
.road-item p { font-size: 14.5px; color: var(--ink-500); }
.road-item .tag { margin-right: 6px; }

/* ---------------- 搜索页 ---------------- */
.search-box {
  display: flex; gap: 10px; margin: 26px 0 8px;
}
.search-box input {
  flex: 1; padding: 12px 18px; font-size: 16px; font-family: var(--font);
  border: 1.5px solid var(--line); border-radius: 10px; outline: none;
  transition: border .15s;
}
.search-box input:focus { border-color: var(--teal-500); }
.search-box button {
  padding: 12px 26px; background: var(--teal-600); color: #fff; border: none;
  border-radius: 10px; font-size: 15px; font-weight: 600; cursor: pointer;
  font-family: var(--font);
}
.search-box button:hover { background: var(--teal-700); }
.search-hint { color: var(--ink-300); font-size: 13.5px; margin-bottom: 18px; }
.result-item {
  background: #fff; border: 1px solid var(--line); border-radius: 10px;
  padding: 16px 20px; margin-bottom: 12px;
}
.result-item h3 { font-size: 16.5px; margin-bottom: 4px; }
.result-item p { font-size: 14px; color: var(--ink-500); }
.result-item mark { background: #fff3c4; padding: 0 2px; border-radius: 3px; }

/* ---------------- 页脚 ---------------- */
.site-footer {
  background: var(--ink-900); color: var(--ink-300);
  padding: 36px 0 30px; margin-top: 30px; font-size: 14px;
}
.footer-inner {
  max-width: 1100px; margin: 0 auto; padding: 0 20px;
  display: flex; flex-wrap: wrap; gap: 30px; justify-content: space-between;
}
.site-footer a { color: #9fc7c2; }
.site-footer .footer-note { max-width: 560px; line-height: 1.8; font-size: 13px; }
.site-footer b { color: #dce9e6; }

/* ---------------- 更新指南页 ---------------- */
.guide-img-demo {
  border: 2px dashed var(--teal-500); border-radius: 10px;
  padding: 18px; background: var(--teal-50); margin: 16px 0;
  font-family: Consolas, monospace; font-size: 14px; line-height: 2;
  overflow-x: auto; white-space: pre;
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 960px) {
  .article-layout { grid-template-columns: minmax(0, 1fr); }
  .toc { position: static; max-height: none; order: 2; border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; background: #fff; min-width: 0; }
  .article { padding: 28px 24px; order: 1; min-width: 0; }
  .nav { gap: 0; }
  .nav a { padding: 6px 8px; font-size: 14px; }
  .nav .nav-text { display: none; }
}
@media (max-width: 640px) {
  .hero h1 { font-size: 26px; }
  .hero { padding: 44px 0 50px; }
  .header-inner { gap: 8px; padding: 0 12px; }
  .logo .sub { display: none; }
  .logo > span { font-size: 13.5px; }
  .nav { gap: 0; overflow-x: auto; scrollbar-width: none; -ms-overflow-style: none; }
  .nav::-webkit-scrollbar { display: none; }
  .nav a { padding: 6px 6px; font-size: 13px; white-space: nowrap; }
  .nav .nav-search { padding: 6px 0 6px 6px; }
  .nav .nav-full { display: none; }
  .nav .nav-short { display: inline; }
  .article { padding: 24px 18px; }
  .article p, .article li { font-size: 15.5px; }
  .article-nav { flex-direction: column; }
}

/* ---------------- 打印 ---------------- */
@media print {
  .site-header, .site-footer, .toc, .article-nav, .filter-bar { display: none !important; }
  .article { border: none; box-shadow: none; padding: 0; }
  body { background: #fff; }
}