:root{--c-bg:#fff;--c-sidebar:#f8f9fa;--c-accent:#d97757;--c-accent-hover:#c5684a;--c-accent-light:#d977571f;--c-border:#cdcdcd;--c-muted:#4e5761;--c-foreground:#111;--c-card:#fff;--radius:8px;--radius-sm:6px;--radius-lg:8px;--shadow:0 2px 12px #0000000f;--topbar-h:56px;--sidebar-w:300px;--toc-w:272px;--font-sans:-apple-system, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;--font-mono:"SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace}*,:before,:after{box-sizing:border-box;margin:0;padding:0}html,body{height:100%;font-family:var(--font-sans);color:var(--c-foreground);background:var(--c-bg);-webkit-font-smoothing:antialiased;font-size:15px}button,input{font:inherit}button{color:inherit}.topbar{height:var(--topbar-h);grid-template-columns:minmax(240px, var(--sidebar-w)) 1fr auto;background:var(--c-bg);border-bottom:1px solid var(--c-border);z-index:300;align-items:center;gap:24px;padding:0 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14px}.brand{cursor:pointer;align-items:center;gap:10px;margin-bottom:16px;display:flex}.brand-icon{flex-shrink:0;width:32px;height:32px}.brand-text{color:var(--c-foreground);letter-spacing:-.01em;font-size:15px;font-weight:700}.sidebar-filter{background:var(--c-bg);height:44px;color:var(--c-muted);border:1px solid #d6d0ca;border-radius:999px;align-items:center;gap:8px;padding:0 14px;display:flex}.sidebar-filter svg{fill:none;stroke:currentColor;stroke-width:2px;stroke-linecap:round;stroke-linejoin:round;flex:none;width:22px;height:22px}.sidebar-filter input{width:100%;min-width:0;color:var(--c-foreground);background:0 0;border:0;outline:0;font-size:16px}.sidebar-nav{-webkit-user-select:none;user-select:none;flex:1;padding:26px 24px 28px;overflow-y:auto}.nav-group{margin-bottom:18px}.nav-group-title{width:100%;color:var(--c-foreground);font-family:var(--font-sans);cursor:pointer;text-align:left;background:0 0;border:none;align-items:center;gap:8px;padding:4px 0 10px;font-size:16px;font-weight:700;transition:background .15s;display:flex}.nav-group-title:hover{color:var(--c-accent);background:0 0}.nav-group-arrow{color:var(--c-muted);flex-shrink:0;font-size:10px;transition:transform .2s}.nav-group-desc{color:var(--c-muted);font-size:11px;font-weight:400}.nav-group.open .nav-group-arrow{transform:rotate(90deg)}.nav-sub{max-height:0;padding-left:20px;list-style:none;transition:max-height .25s;overflow:hidden}.nav-group.open .nav-sub{max-height:600px}.nav-sub li{margin:1px 0}.nav-sub a{color:var(--c-foreground);cursor:pointer;-webkit-user-select:none;user-select:none;cursor:pointer;border-left:3px solid #0000;border-radius:0;padding:8px 0;font-size:15px;text-decoration:none;transition:all .15s;display:block}.nav-sub a:hover{color:var(--c-accent);background:0 0}.nav-sub 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