*{box-sizing:border-box;margin:0;padding:0}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'PingFang SC','Microsoft YaHei',sans-serif;background:#f5f5f5;display:flex;flex-direction:column;height:100vh;overflow:hidden}
.topbar{background:#2a5fc4;color:#fff;padding:10px 16px;display:flex;align-items:center;gap:10px;flex-shrink:0;transition:margin-top .2s}
.topbar.hidden{visibility:hidden} /* 正文下滑后整条收起（margin-top 由 post.js 设为负的自身高度），回到顶部再出现 */
.float-back{position:fixed;top:calc(10px + env(safe-area-inset-top));right:12px;z-index:30;width:40px;height:40px;border-radius:50%;background:#2a5fc4;color:#fff;display:flex;align-items:center;justify-content:center;box-shadow:0 2px 8px rgba(0,0,0,.2);opacity:0;pointer-events:none;transform:scale(.8);transition:opacity .2s,transform .2s}
.float-back.show{opacity:1;pointer-events:auto;transform:none}
.topbar a{color:rgba(255,255,255,.85);text-decoration:none;font-size:14px}
.topbar a:hover{color:#fff}
.topbar .sep{color:rgba(255,255,255,.4)}
.topbar .filename{font-weight:700;font-size:15px;flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.btn-dl{background:rgba(255,255,255,.2);border:1px solid rgba(255,255,255,.45);color:#fff!important;padding:5px 12px;border-radius:5px;font-size:13px;cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;gap:4px;flex-shrink:0}
.btn-dl:hover{background:rgba(255,255,255,.35)}
.btn-icon{width:34px;padding:5px;justify-content:center}
.btn-danger{color:#ffaaaa!important;border-color:rgba(255,100,100,.5)}
.layout{display:flex;flex:1;overflow:hidden;position:relative}
#tocSidebar{width:220px;background:#fff;border-right:1px solid #e2e8f0;overflow-y:auto;padding:16px 12px;flex-shrink:0;transition:transform .25s}
#tocSidebar h3{font-size:12px;text-transform:uppercase;color:#aaa;letter-spacing:.8px;margin-bottom:10px}
#tocList{list-style:none}
#tocList li a{display:block;padding:3px 6px;border-radius:4px;font-size:13px;color:#555;text-decoration:none;line-height:1.5}
#tocList li a:hover{background:#eff6ff;color:#2a5fc4}
#tocList li a.active{background:#eff6ff;color:#2a5fc4;font-weight:600}
.toc-h2{padding-left:10px!important}
.toc-h3{padding-left:20px!important}
.toc-h4{padding-left:30px!important}
#contentArea{flex:1;overflow-y:auto;padding:32px;max-width:1080px;margin:0 auto;width:100%}
#contentArea.wide-mode{max-width:100%}
.post-title{margin:4px 4px 10px;text-align:center;font-size:26px;line-height:1.4;color:#2a5fc4;word-break:break-word}
.post-meta{font-size:12.5px;color:#999;margin:0 4px 14px;display:flex;gap:8px;align-items:center;justify-content:center;flex-wrap:wrap}
.tag{background:#fff4e5;color:#c77700;padding:0 6px;border-radius:4px}
#mdBody{background:#fff;padding:32px;border-radius:8px;box-shadow:0 1px 4px rgba(0,0,0,.08);min-height:200px;line-height:1.7;color:#333;word-break:break-word}
#mdBody pre{background:#f6f8fa;border:1px solid #e1e4e8;border-radius:6px;padding:16px;overflow-x:auto;font-size:14px;line-height:2;letter-spacing:.3px;margin:16px 0;position:relative}
#mdBody code{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'PingFang SC','Microsoft YaHei',sans-serif;font-size:.9em;background:#f6f8fa;padding:2px 5px;border-radius:3px}
#mdBody pre code{background:none;padding:0}
#mdBody pre.md-mermaid{white-space:pre-wrap}
#mdBody pre.md-mermaid.ok{background:none;border:none;padding:0;text-align:center;white-space:normal;line-height:normal;letter-spacing:normal}
#mdBody pre.md-mermaid.ok svg{max-width:100%;height:auto}
#mdBody pre.md-mermaid.bad{border-color:#f0b4b4}
#mdBody h1,#mdBody h2,#mdBody h3,#mdBody h4{margin:24px 0 12px;color:#2a5fc4}
#mdBody>:first-child{margin-top:0}
#mdBody h2{border-bottom:1px solid #eee;padding-bottom:6px}
#mdBody p{margin:0 0 12px}
#mdBody ul,#mdBody ol{margin:0 0 12px 24px}
#mdBody blockquote{border-left:4px solid #2a5fc4;margin:0 0 12px;padding:8px 16px;background:#eff6ff;border-radius:0 4px 4px 0;color:#555}
#mdBody table{border-collapse:collapse;width:100%;margin:16px 0;display:block;overflow-x:auto}
#mdBody th,#mdBody td{border:1px solid #ddd;padding:8px 12px}
#mdBody th{background:#f8f9fa}
#mdBody a{color:#2a5fc4}
#mdBody hr{border:none;border-top:1px solid #ddd;margin:20px 0}
#mdBody img{max-width:100%;border-radius:4px;cursor:zoom-in}
#mdBody img.broken{min-width:120px;min-height:60px;border:1px dashed #ccc;background:#fafafa}
/* 文章卡片底部中央的「回到文章开头」圆形按钮（半叠在卡片下边缘上） */
.back-top{display:flex;align-items:center;justify-content:center;width:44px;height:44px;margin:-22px auto 0;border-radius:50%;border:1px solid #e1e4e8;background:#fff;color:#2a5fc4;cursor:pointer;box-shadow:0 1px 4px rgba(0,0,0,.1);transition:background .15s,color .15s,border-color .15s,transform .15s}
.back-top:hover{background:#2a5fc4;border-color:#2a5fc4;color:#fff;transform:translateY(-2px)}
.back-top:active{transform:translateY(0)}
.back-top svg{width:20px;height:20px}
.copy-code-btn{position:absolute;top:8px;right:8px;padding:3px 10px;font-size:12px;border:1px solid #d0d7de;border-radius:4px;background:rgba(246,248,250,.9);color:#57606a;cursor:pointer;opacity:0;transition:opacity .15s;line-height:1.6;font-family:sans-serif}
#mdBody pre:hover .copy-code-btn{opacity:1}
.copy-code-btn:hover{background:#eaf0fb;border-color:#2a5fc4;color:#2a5fc4}
.copy-code-btn.copied{background:#e6ffed;border-color:#52c41a;color:#389e0d;opacity:1}
.toc-toggle{display:none}
#imgViewer{display:none;position:fixed;inset:0;background:rgba(0,0,0,.85);z-index:300;align-items:center;justify-content:center;cursor:zoom-out;padding:20px}
#imgViewer.open{display:flex}
#imgViewer img{max-width:100%;max-height:100%;box-shadow:0 8px 40px rgba(0,0,0,.5)}
@media(max-width:768px){
  /* 手机改成整页滚动（不在 #contentArea 里滚）：浏览器只在文档滚动时才自动收起地址栏 */
  body{display:block;height:auto;overflow:visible}
  .layout{display:block;overflow:visible}
  #contentArea{overflow:visible}
  .topbar{position:sticky;top:0;z-index:50;transition:transform .2s}
  .topbar.hidden{transform:translateY(-100%)}
  #tocSidebar{position:fixed;top:0;bottom:0;left:0;z-index:100;transform:translateX(-100%)}
  #tocSidebar.open{transform:translateX(0);box-shadow:2px 0 8px rgba(0,0,0,.15)} /* 阴影只在打开时有，收起时不会在屏幕左缘露一条灰边 */
  .toc-toggle{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border-radius:6px;border:1px solid rgba(255,255,255,.45);background:rgba(255,255,255,.18);cursor:pointer;flex-shrink:0;color:#fff}
  #contentArea{padding:16px}
  #mdBody{padding:16px}
  .post-title{font-size:21px;margin-top:0}
  .topbar{padding:10px 10px;gap:6px}
  .topbar .crumb,.topbar .sep{display:none}
  /* 手机顶栏不显示标题（正文区已有大标题），只留一排图标，压矮到约 44px；标题仍占位把按钮推到右侧 */
  .topbar{padding-top:6px;padding-bottom:6px}
  .topbar .filename{visibility:hidden}
  #btnDownload,#btnWidth{display:none} /* 手机端不显示下载与切换宽窄 */
  .btn-dl-text{display:none}
  a.btn-dl{padding:5px;width:34px;justify-content:center}
  .copy-code-btn{opacity:1}
}