:root{--bg: #070b16;--bg2: #0c1322;--card: rgba(18, 26, 44, .72);--card-solid: #111b2e;--ink: #e7eefb;--ink-soft: #9bb0cf;--brand: #38bdf8;--brand2: #818cf8;--brand-glow: rgba(56, 189, 248, .45);--line: rgba(120, 165, 230, .16);--radius: 18px;--radius-sm: 12px;--shadow: 0 10px 40px rgba(0, 0, 0, .45);--font: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", sans-serif;--mono: "JetBrains Mono", "Fira Code", "Cascadia Code", Consolas, monospace}*{box-sizing:border-box}html,body{margin:0;padding:0;background:var(--bg);color:var(--ink);font-family:var(--font);font-size:18px;line-height:1.75;-webkit-font-smoothing:antialiased}.bg-grid{position:fixed;inset:0;z-index:0;pointer-events:none;background:radial-gradient(1200px 600px at 80% -10%,rgba(56,189,248,.12),transparent 60%),radial-gradient(1000px 500px at 0% 110%,rgba(129,140,248,.12),transparent 60%),linear-gradient(var(--line) 1px,transparent 1px) 0 0 / 100% 44px,linear-gradient(90deg,var(--line) 1px,transparent 1px) 0 0 / 44px 100%;opacity:.5}main{position:relative;z-index:1}h1,h2,h3{line-height:1.35;font-weight:700}a{color:inherit;text-decoration:none}.top-nav{display:flex;align-items:center;gap:16px;padding:14px 28px;background:#080d18c7;backdrop-filter:blur(12px);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}.top-nav .logo{font-size:22px;font-weight:800;letter-spacing:.5px;color:var(--ink);display:flex;align-items:center;gap:9px}.top-nav .logo .logo-mark{color:var(--brand);font-size:18px;text-shadow:0 0 14px var(--brand-glow)}.top-nav .nav-links{margin-left:auto;display:flex;gap:22px;font-size:17px;font-weight:600;color:var(--ink-soft)}.top-nav .nav-links a{position:relative;padding:4px 2px}.top-nav .nav-links a:hover{color:var(--brand)}.top-nav .nav-links a:after{content:"";position:absolute;left:0;right:0;bottom:-4px;height:2px;background:var(--brand);transform:scaleX(0);transition:transform .2s ease;box-shadow:0 0 10px var(--brand-glow)}.top-nav .nav-links 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