*{box-sizing:border-box}
body{margin:0;font:16px/1.6 -apple-system,Segoe UI,Roboto,sans-serif;color:#222}
.layout{display:flex;min-height:100vh}
.sidebar{width:300px;background:#f7f7f9;border-right:1px solid #e5e5e5;
  padding:20px;overflow-y:auto;position:sticky;top:0;height:100vh}
.brand{font-weight:700;font-size:1.2em;margin-bottom:15px;color:#0052cc}
.content{flex:1;padding:40px 60px;max-width:900px}
.nav{list-style:none;padding-left:0;margin:0}
.nav .nav{padding-left:16px;border-left:1px solid #e0e0e0;margin-left:6px}
.nav li{margin:4px 0}
.nav a{text-decoration:none;color:#333}
.nav a:hover{color:#0052cc}
.nav li.active>a{color:#0052cc;font-weight:600}
.folder-title{font-weight:600;color:#555;font-size:.95em;display:block;margin-top:8px}
.siblings{margin-top:40px;padding:20px;background:#fafbff;
  border:1px solid #e5e8ff;border-radius:8px}
.siblings h2{margin-top:0}
.siblings li{margin:6px 0}
table{border-collapse:collapse}
th,td{border:1px solid #ddd;padding:6px 10px}
code{background:#f0f0f0;padding:2px 5px;border-radius:3px}