:root{
  --bg:#f3f5fb;--panel:#111827;--card:#fff;--ink:#111827;--muted:#64748b;--line:#e5e7eb;
  --soft:#f8fafc;--blue:#4f46e5;--violet:#7c3aed;--cyan:#0891b2;--green:#059669;
  --shadow:0 18px 50px rgba(79,70,229,.16);
}
*{box-sizing:border-box}
html{max-width:100%;overflow-x:hidden;scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);line-height:1.65;font-family:-apple-system,BlinkMacSystemFont,"Apple SD Gothic Neo","Malgun Gothic",sans-serif}
a{color:inherit;text-decoration:none}
.top{position:sticky;top:0;z-index:10;display:flex;justify-content:space-between;gap:20px;align-items:center;padding:14px 22px;background:rgba(15,23,42,.94);backdrop-filter:blur(10px);color:white}
.top strong{display:block;font-size:16px}.top span{display:block;color:#a5b4fc;font-size:12px}.top nav{display:flex;gap:8px;flex-wrap:wrap}.top a{color:#dbeafe;text-decoration:none;font-size:13px;padding:6px 9px;border-radius:999px}.top a.active,.top a:hover{background:#312e81;color:#fff}
.wrap{max-width:1180px;margin:0 auto;padding:26px 18px 84px}.sf{position:absolute;left:-9999px;opacity:0;width:0;height:0}
.site{background:linear-gradient(135deg,#4f46e5,#7c3aed);color:white;border-radius:22px;padding:30px;margin-bottom:18px;box-shadow:var(--shadow)}
.site h1{font-size:30px;font-weight:850;margin:.1rem 0;letter-spacing:-.6px}.site .tag{margin:.35rem 0 0;color:#e0e7ff}.site::before{content:"STUDY";display:block;font-size:12px;font-weight:800;letter-spacing:.12em;opacity:.8;margin-bottom:4px}
.banner{display:block;background:#eef2ff;border:1px solid #c7d2fe;border-radius:16px;padding:13px 16px;margin:0 0 18px;font-size:14px;color:#312e81;font-weight:800}.banner:hover{background:#e0e7ff}.banner .when{color:#64748b;font-weight:700}
.filters{display:flex;flex-wrap:wrap;gap:8px;align-items:center;background:#fff;border:1px solid var(--line);border-radius:16px;padding:14px;margin:0 0 18px;box-shadow:0 10px 26px rgba(15,23,42,.04)}
.filters .fcap{color:var(--muted);font-size:12px;font-weight:800;margin-right:2px}.filters label{border:1px solid var(--line);background:#fff;color:#475569;border-radius:999px;padding:7px 13px;font-size:13px;font-weight:750;cursor:pointer;transition:.15s}.filters label:hover{border-color:#c7d2fe;color:#312e81;background:#eef2ff}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}.card{display:flex;flex-direction:column;gap:8px;background:var(--card);border:1px solid var(--line);border-radius:18px;padding:18px 18px 16px;transition:.18s;min-height:150px;box-shadow:0 10px 28px rgba(15,23,42,.04)}.card:hover{transform:translateY(-3px);box-shadow:0 18px 44px rgba(79,70,229,.14);border-color:#c7d2fe}.card .emoji{font-size:26px}.card h3{font-size:17px;margin:0;font-weight:850}.card .sum{font-size:13.5px;color:#4b5563;margin:0;flex:1}.card .meta{font-size:12px;color:var(--muted);font-weight:800}
.home{display:inline-flex;align-items:center;margin:0 0 14px;font-size:13px;font-weight:800;color:#312e81;background:#eef2ff;border:1px solid #c7d2fe;border-radius:999px;padding:7px 11px}.home:hover{background:#312e81;color:#fff}.book{display:grid;grid-template-columns:280px minmax(0,1fr);gap:22px;align-items:start}.toc{position:sticky;top:76px;border:1px solid var(--line);background:#fff;border-radius:18px;padding:16px 16px;font-size:13.5px;box-shadow:0 10px 28px rgba(15,23,42,.05)}.toc-h{font-weight:850;margin-bottom:10px}.toc ul{margin:0;padding-left:0;list-style:none;display:flex;flex-direction:column;gap:7px}.toc a{display:block;color:#475569;border-radius:10px;padding:6px 8px}.toc a:hover{background:#eef2ff;color:#312e81}.toc a.cur{color:#312e81;background:#eef2ff;font-weight:850}.toc .dft{color:#9aa3b2;font-size:11px;border:1px solid var(--line);border-radius:6px;padding:0 5px}.reader{min-width:0;background:#fff;border:1px solid var(--line);border-radius:22px;padding:28px 30px;box-shadow:0 12px 32px rgba(15,23,42,.05)}.reader .label{font-size:12px;font-weight:850;letter-spacing:.08em;color:var(--cyan);text-transform:uppercase}.reader h1{font-size:30px;font-weight:850;margin:6px 0 18px;letter-spacing:-.45px}.reader h2{font-size:22px;margin:30px 0 10px}.reader h3{font-size:18px;margin:22px 0 8px}.reader p{margin:12px 0}.reader ul,.reader ol{margin:12px 0;padding-left:22px}.reader blockquote{margin:14px 0;padding:8px 15px;border-left:3px solid var(--blue);background:#f8fafc;color:#475569}.reader code{background:#eef2f7;padding:1px 6px;border-radius:6px;font-family:"SF Mono",ui-monospace,Menlo,monospace;font-size:.92em}.reader pre{background:#0f172a;color:#e2e8f0;padding:14px 16px;border-radius:12px;overflow:auto;margin:14px 0}.reader pre code{background:none;padding:0;color:inherit}.reader table{border-collapse:collapse;margin:14px 0;width:100%}.reader th,.reader td{border:1px solid var(--line);padding:7px 10px;text-align:left;font-size:14px}.reader th{background:#f1f5f9}.reader hr{border:none;border-top:1px solid var(--line);margin:24px 0}
.reader .diagram{margin:22px 0;padding:18px 16px;border:1px solid var(--line);border-radius:14px;background:#fbfcfe;overflow-x:auto;text-align:center;container-type:inline-size}.reader .diagram svg{max-width:100%;height:auto}.reader .diagram figcaption{margin-top:12px;font-size:12.5px;color:var(--muted);font-weight:700}.diagram .flow{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px}.diagram .col{display:flex;flex-direction:column;gap:10px;align-items:center}.diagram .node{display:inline-flex;align-items:center;justify-content:center;text-align:center;padding:10px 14px;border:1.5px solid var(--blue);border-radius:10px;background:#fff;font-size:13px;font-weight:750;color:var(--ink);min-width:84px}.diagram .node.alt{border-color:var(--green);background:#f0fdfa}.diagram .node.dim{border-color:var(--line);color:var(--muted);font-weight:600;background:#fff}.diagram .arrow{display:inline-block;color:var(--muted);font-weight:800;font-size:18px;line-height:1;transform:rotate(90deg)}.diagram .group{border:1.5px dashed var(--line);border-radius:12px;padding:12px;display:flex;flex-direction:column;gap:10px;align-items:center}.diagram .group .lbl{font-size:11px;font-weight:800;color:var(--muted);letter-spacing:.04em}@container (min-width:520px){.diagram .flow{flex-direction:row;flex-wrap:nowrap}.diagram .arrow{transform:none}}
.pager{display:flex;align-items:center;justify-content:space-between;margin:34px 0 6px;font-size:14px;font-weight:800}.pager .nav{color:#312e81}.pager .nav.off{color:#c2c8d2}.pager .pos{color:var(--muted);font-weight:850}.bar{height:6px;background:#e8edf4;border-radius:999px;overflow:hidden}.bar i{display:block;height:100%;background:linear-gradient(90deg,var(--blue),var(--violet))}
@media(max-width:820px){.top{align-items:flex-start;flex-direction:column}.book{grid-template-columns:1fr}.toc{position:static}.reader{padding:22px 18px}}