:root{
  --bg:#0d1117;
  --bg-alt:#131a24;
  --card:#1a2230;
  --card-2:#212b3d;
  --border:#2c3750;
  --text:#e8ecf3;
  --text-dim:#a5afc4;
  --text-faint:#7c88a3;
  --accent:#4f8cff;
  --accent-2:#22c1a3;
  --warn-bg:#3a2b1d;
  --warn-border:#b07a2e;
  --note-bg:#1c2a3a;
  --note-border:#2e6fb7;
  --tip-bg:#16322e;
  --tip-border:#1f8f74;
  --shadow:0 4px 24px rgba(0,0,0,.45);
}
*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  background:var(--bg);
  color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  font-size:17.5px;line-height:1.8;
}
a{color:var(--accent);text-decoration:none;}
a:hover{color:#7faeff;text-decoration:underline;}

/* ===== 顶部网站导航 ===== */
.head{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  background:rgba(13,17,23,.92);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border);
}
.topbar{
  max-width:1500px;margin:0 auto;padding:0 20px;
  display:flex;align-items:center;gap:24px;height:60px;
}
.app-logo a{display:flex;align-items:center;color:var(--text);}
.app-logo svg{width:34px;height:34px;margin-right:10px;}
.app-logo span{font-size:18px;font-weight:700;letter-spacing:.3px;}
.topnav{display:flex;align-items:center;gap:4px;margin-left:8px;flex:1;flex-wrap:wrap;}
.topnav a{
  color:var(--text-dim);padding:8px 14px;border-radius:8px;font-size:16px;
  transition:color .15s,background .15s;
}
.topnav a:hover{color:var(--text);background:var(--card);text-decoration:none;}
.topnav a.active{color:#fff;background:var(--card-2);font-weight:600;}
.topsearch{position:relative;}
.topsearch input{
  background:var(--card);border:1px solid var(--border);border-radius:8px;
  color:var(--text);padding:8px 14px 8px 34px;width:200px;font-size:15px;outline:none;
  transition:border-color .15s,width .2s;
}
.topsearch input:focus{border-color:var(--accent);width:240px;}
.topsearch svg{position:absolute;left:10px;top:50%;transform:translateY(-50%);width:16px;height:16px;color:var(--text-faint);pointer-events:none;}

/* ===== 主布局: 左侧广告 | 教程导航 | 内容 | related apps ===== */
.layout{
  max-width:1500px;margin:0 auto;padding:84px 20px 40px;
  display:grid;
  grid-template-columns:150px 270px minmax(0,1fr) 280px;
  gap:24px;
  align-items:start;
}

/* 最左侧固定广告单元（sticky，随窗口滚动，无背景无标签保持干净） */
.left-ad{
  position:sticky;top:84px;
  min-height:300px;text-align:center;
}
.left-ad .adsbygoogle{min-height:280px;}

/* 左侧教程导航（目录树） */
.toc{
  position:sticky;top:84px;
  background:var(--bg-alt);border:1px solid var(--border);border-radius:12px;
  padding:16px 12px;max-height:calc(100vh - 110px);overflow:auto;
}
.toc-title{
  display:flex;align-items:center;gap:8px;
  font-size:14px;font-weight:700;color:var(--accent-2);
  text-transform:uppercase;letter-spacing:1.2px;margin-bottom:8px;
}
.toc-title svg{width:14px;height:14px;}
.toc a{
  display:block;padding:6px 10px;border-radius:8px;margin:1px 0;
  color:var(--text-dim);font-size:14.5px;border-left:3px solid transparent;
  transition:background .15s,color .15s,border-color .15s;line-height:1.45;
}
.toc a:hover{background:var(--card);color:var(--text);text-decoration:none;}
.toc a.active{background:var(--card-2);color:#fff;border-left-color:var(--accent);}
.toc a.l2{padding-left:22px;font-size:14px;}
.toc a.l3{padding-left:34px;font-size:13.5px;}

/* 目录树分组层级 */
.toc-group{
  margin:2px 0;color:var(--text);
}
.toc-group summary{
  display:flex;align-items:center;gap:6px;cursor:pointer;
  padding:7px 10px;border-radius:8px;
  font-size:14px;font-weight:650;line-height:1.4;list-style:none;
  transition:background .15s,color .15s;
}
.toc-group summary::-webkit-details-marker{display:none;}
.toc-group summary:hover{background:var(--card);color:#fff;}
.toc-caret{
  color:var(--accent-2);font-size:11px;flex-shrink:0;
  transition:transform .2s ease;
}
.toc-group[open] > summary .toc-caret{transform:rotate(90deg);}
.toc-group > summary .toc-caret{transform:rotate(0deg);}

/* 顶层模块分组（l0）：强调色块 + 左边框，模块间分隔线 */
.toc-group.l0{
  margin:8px 0;border-top:1px solid var(--border);padding-top:6px;
}
.toc-group.l0:first-child{border-top:none;margin-top:0;padding-top:0;}
.toc-group.l0 > summary{
  font-weight:750;font-size:14.5px;color:#fff;
  background:var(--card-2);border-left:3px solid var(--accent);
  padding:8px 10px;
}
.toc-group.l0 > summary:hover{background:#28344c;}

/* 嵌套分组（l1+）：树状缩进 + 连接线 */
.toc details details{
  margin-left:12px;padding-left:8px;
  border-left:1px solid var(--border);
  margin-top:1px;margin-bottom:1px;
}
.toc details details > summary{
  font-weight:600;font-size:13.8px;color:var(--text);
  padding:5px 8px;
}
.toc details details > summary .toc-caret{color:var(--text-faint);}
.toc details details a{font-size:13.8px;}

/* 链接逐级缩进：与所属分组对齐 */
.toc a{padding-left:18px;}
.toc a.l2{padding-left:30px;}
.toc a.l3{padding-left:42px;}

/* 中间内容 */
.content{
  background:var(--card);border:1px solid var(--border);border-radius:12px;
  padding:36px 40px;min-width:0;box-shadow:var(--shadow);
}
.content h1{font-size:31px;line-height:1.35;margin:0 0 16px;font-weight:800;padding-bottom:14px;border-bottom:1px solid var(--border);}
.content h2{font-size:23.5px;margin:30px 0 12px;padding-top:18px;border-top:1px solid var(--border);font-weight:700;}
.content h2:first-of-type{border-top:none;padding-top:0;margin-top:18px;}
.content h3{font-size:19.5px;margin:22px 0 10px;font-weight:650;}
.content h4{font-size:17.5px;margin:18px 0 8px;font-weight:650;color:var(--accent-2);}
.content p{margin:0 0 14px;}
.content ul,.content ol{margin:0 0 16px 26px;}
.content li{margin-bottom:7px;}
.content .emph{font-style:italic;font-weight:600;}
.content .input{
  display:inline-block;background:#0c1119;border:1px solid var(--border);border-radius:6px;
  padding:2px 10px;font-family:Consolas,Menlo,monospace;color:#7fd4c1;cursor:pointer;
  box-shadow:inset 0 1px 3px rgba(0,0,0,.4);
}
.content .input:hover{border-color:var(--accent-2);}
.content pre{
  background:#0c1119;border:1px solid var(--border);border-radius:8px;
  padding:14px 16px;overflow:auto;margin:0 0 16px;
  font-family:Consolas,Menlo,monospace;font-size:14.5px;color:#9fd4c4;
}
.content code{font-family:Consolas,Menlo,monospace;background:#0c1119;padding:1px 6px;border-radius:4px;color:#7fd4c1;font-size:14.5px;}
.content pre code{background:none;padding:0;color:inherit;}
.content img{max-width:100%;height:auto;border-radius:8px;}

/* 表格 */
.content table{border-collapse:collapse;width:100%;margin:0 0 18px;font-size:15.5px;display:block;overflow-x:auto;}
.content table th,.content table td{border:1px solid var(--border);padding:9px 12px;text-align:left;vertical-align:top;}
.content table th{background:var(--card-2);font-weight:650;color:#fff;}
.content table tr:nth-child(even) td{background:rgba(255,255,255,.02);}
.content table p{margin:0 0 4px;}
.content table p:last-child{margin:0;}

/* 提示框 */
.callout{display:flex;gap:14px;border-radius:10px;padding:14px 16px;margin:18px 0;border:1px solid;align-items:flex-start;}
.callout .ico{flex-shrink:0;margin-top:2px;}
.callout .ico svg{width:22px;height:22px;}
.callout p{margin:0;}
.callout.warning{background:var(--warn-bg);border-color:var(--warn-border);}
.callout.warning .ico{color:#e8a33d;}
.callout.note{background:var(--note-bg);border-color:var(--note-border);}
.callout.note .ico{color:#5f9dea;}
.callout.tip{background:var(--tip-bg);border-color:var(--tip-border);}
.callout.tip .ico{color:#35c9a6;}
.warning,.note,.tip{border-radius:10px;padding:14px 16px;margin:18px 0;border:1px solid;}
.warning{background:var(--warn-bg);border-color:var(--warn-border);}
.note{background:var(--note-bg);border-color:var(--note-border);}
.tip{background:var(--tip-bg);border-color:var(--tip-border);}
.warning p,.note p,.tip p{margin:0;}

/* 相关主题 (Related Topics) */
.relatedtopics{
  margin:26px 0 10px;padding:16px 18px;
  background:var(--bg-alt);border:1px solid var(--border);border-left:3px solid var(--accent);
  border-radius:10px;
}
.relatedtopics .related{
  font-weight:700;color:var(--accent-2);font-size:14px;
  text-transform:uppercase;letter-spacing:1px;margin-bottom:10px;
}
.relatedtopics .related a{color:var(--accent-2);text-decoration:none;}
.relatedtopics .relatedbody p{margin:4px 0;font-size:15px;}
.relatedtopics .relatedbody a{display:inline-block;padding:2px 0;}
.relatedtopics .relatedbody .embedded{margin:4px 0;}

/* 命令访问路径 (To access this command...) */
.howtoget{
  margin:18px 0;padding:14px 16px;
  background:var(--bg-alt);border-left:3px solid var(--border);
  border-radius:10px;
}
.howtoget .howtogetheader{font-weight:700;color:var(--text);margin-bottom:6px;}
.howtoget .howtogetbody p{margin:4px 0;font-size:15px;}

/* 广告单元（内容中穿插，无背景无标签保持干净） */
.ad-block{
  margin:26px 0;text-align:center;min-height:120px;
}
.ad-block .adsbygoogle{min-height:120px;}

/* 右侧 related apps */
.related{position:sticky;top:84px;display:flex;flex-direction:column;gap:20px;max-height:calc(100vh - 110px);overflow:auto;}
.related-block{background:var(--bg-alt);border:1px solid var(--border);border-radius:12px;padding:16px;}
.related-title{display:flex;align-items:center;gap:8px;font-size:14px;font-weight:700;color:var(--accent-2);text-transform:uppercase;letter-spacing:1.2px;margin-bottom:12px;}
.related-title svg{width:14px;height:14px;}
.related p{color:var(--text-dim);font-size:14.5px;margin:0;}
.related ul{list-style:none;margin:0;padding:0;}
.related .rapp{display:flex;gap:10px;align-items:center;padding:8px;border-radius:8px;transition:background .15s;}
.related .rapp:hover{background:var(--card);}
.related .rapp img{width:42px;height:42px;border-radius:8px;flex-shrink:0;background:#fff;object-fit:contain;}
.related .rapp h4{font-size:14.5px;color:var(--text);font-weight:600;line-height:1.35;margin:0;}
.related .rapp a{color:inherit;}
.related .rapp a:hover{text-decoration:none;color:var(--accent);}
.related .rapp .adsbygoogle{min-height:200px;}

/* 模块入口卡片（主页） */
.mod-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px;margin-top:10px;}
.mod-card{background:var(--bg-alt);border:1px solid var(--border);border-radius:12px;padding:18px;}
.mod-card h3{font-size:17.5px;margin:0 0 6px;}
.mod-card p{color:var(--text-dim);font-size:14px;margin:0 0 12px;}
.btn-store{
  display:inline-block;margin-top:12px;background:var(--accent);color:#fff;
  padding:8px 18px;border-radius:8px;font-weight:600;font-size:15px;
  transition:background .15s,transform .15s;
}
.btn-store:hover{background:#3d7bf0;color:#fff;text-decoration:none;transform:translateY(-1px);}

/* 底部 */
.footer{border-top:1px solid var(--border);background:var(--bg-alt);padding:26px 20px;text-align:center;color:var(--text-faint);font-size:15px;}
.footer a{color:#6ea3f7;margin-left:24px;}
.footer a:first-of-type{margin-left:0;}
.footer-attribution{
  max-width:900px;margin:0 auto 12px;
  font-size:12.5px;line-height:1.7;color:var(--text-faint);
}
.footer-attribution a{color:#6ea3f7;margin:0;text-decoration:underline;}

/* 响应式 */
@media (max-width:1280px){
  .layout{grid-template-columns:130px 250px minmax(0,1fr) 250px;gap:18px;}
  .content{padding:30px 28px;}
}
@media (max-width:1100px){
  .layout{grid-template-columns:260px minmax(0,1fr);}
  .left-ad{display:none;}
  .related{position:static;grid-column:1 / -1;max-height:none;flex-direction:row;flex-wrap:wrap;}
  .related-block{flex:1 1 300px;}
}
@media (max-width:820px){
  .layout{grid-template-columns:1fr;padding-top:70px;}
  .toc{position:static;max-height:none;}
  .topnav{display:none;}
  .topsearch{display:none;}
  .content{padding:24px 18px;}
  .related{grid-column:auto;flex-direction:column;}
}

a.mod-card{color:inherit;text-decoration:none;display:block;transition:border-color .15s ease;}
a.mod-card:hover{border-color:var(--accent);}
.help-back{margin:0 0 10px;font-size:14.5px;}
.help-back a{color:var(--accent);text-decoration:none;}
.help-back a:hover{text-decoration:underline;}