:root{
  --bg:#0b0e14;
  --card:#101826;
  --text:#e8edf6;
  --muted:#a7b1c2;
  --accent:#8bd5ff;
  --border:rgba(255,255,255,.08);
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  line-height:1.7;
  background:radial-gradient(900px 600px at 20% 10%, #14233a, transparent), var(--bg);
  color:var(--text);
}
.container{max-width:900px;margin:0 auto;padding:18px}
.site-header{position:sticky;top:0;background:rgba(11,14,20,.85);backdrop-filter: blur(10px);border-bottom:1px solid var(--border)}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:12px}
.brand{color:var(--text);text-decoration:none;font-weight:700;letter-spacing:.2px}
.nav a{color:var(--muted);text-decoration:none;margin-left:12px}
.nav a:hover{color:var(--text)}

.card{
  background: linear-gradient(180deg, rgba(255,255,255,.04), rgba(255,255,255,.02));
  border:1px solid var(--border);
  border-radius:16px;
  padding:18px 18px;
  box-shadow: 0 10px 30px rgba(0,0,0,.25);
}
.muted{color:var(--muted)}

.toc{padding-left:20px;margin:10px 0 0}
.toc-item{margin:6px 0}
.toc-link{display:flex;gap:10px;align-items:baseline;color:var(--text);text-decoration:none;padding:10px 12px;border-radius:12px;border:1px solid transparent}
.toc-link:hover{border-color:var(--border);background:rgba(255,255,255,.03)}
.toc-id{font-variant-numeric: tabular-nums; color: var(--accent); min-width: 4.5ch}
.toc-title{color: var(--text)}

.chap-nav{display:flex;justify-content:space-between;gap:10px;margin:14px 0}
.btn{
  display:inline-block;
  padding:10px 12px;
  border-radius:12px;
  border:1px solid var(--border);
  text-decoration:none;
  color:var(--text);
  background:rgba(255,255,255,.03);
}
.btn:hover{background:rgba(255,255,255,.06)}
.btn.disabled{opacity:.45;pointer-events:none}

.chap-title{margin:8px 0 12px}
.chap-meta{font-size:.95rem}
.chap-content :where(p,ul,ol){margin:12px 0}
.chap-content h1,.chap-content h2,.chap-content h3{margin:18px 0 10px;line-height:1.25}
.chap-content pre{padding:12px;border-radius:12px;background:#0d1320;border:1px solid var(--border);overflow:auto}
.chap-content code{background:#0d1320;padding:2px 6px;border-radius:8px;border:1px solid var(--border)}
.chap-content blockquote{margin:12px 0;padding:8px 12px;border-left:3px solid rgba(139,213,255,.55);color:var(--muted)}
.chap-content a{color:var(--accent)}

.site-footer{margin-top:18px;border-top:1px solid var(--border)}