:root{--bg:#f4f7fb;--surface:#fff;--ink:#172238;--muted:#60708a;--line:#d9e2ef;--primary:#3157d5;--primary2:#6c4ee3;--soft:#eaf0ff;--good:#087f5b;--bad:#c23535;--shadow:0 16px 42px rgba(37,55,91,.1)}[data-theme=dark]{--bg:#111827;--surface:#1c2637;--ink:#eef4ff;--muted:#aebbd0;--line:#35445b;--primary:#86a5ff;--primary2:#aa91ff;--soft:#253554;--good:#5ee6b3;--bad:#ff8b8b;--shadow:0 16px 42px rgba(0,0,0,.25)}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.55 system-ui,-apple-system,"Segoe UI",sans-serif}.site-header{background:linear-gradient(115deg,#203f9e,#7149b9);color:white}.header-inner{max-width:1160px;margin:auto;padding:24px;display:flex;justify-content:space-between;align-items:center}.header-inner h1,.header-inner p{margin:0}.header-inner p{opacity:.82}.icon-btn{width:42px;height:42px;border:1px solid #ffffff55;border-radius:50%;color:white;background:#ffffff18;font-size:20px}.section-nav{display:flex;justify-content:center;gap:8px;padding:12px;position:sticky;top:0;z-index:5;background:color-mix(in srgb,var(--surface) 94%,transparent);border-bottom:1px solid var(--line)}.nav-btn,.btn{border:1px solid var(--line);border-radius:12px;padding:10px 15px;background:var(--surface);color:var(--ink);font-weight:750;cursor:pointer}.nav-btn.active,.btn.primary{background:var(--primary);border-color:var(--primary);color:white}.btn.danger{color:var(--bad)}main{width:min(1120px,calc(100% - 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