:root{--bg: #f7f8fb;--surface: #ffffff;--border: #e6e8ef;--text: #1a1d29;--muted: #6b7180;--brand: #4f46e5;--brand-soft: #eef0fe;--brand-ink: #3730a3;--accent: #0ea5a4;--radius: 14px;--shadow: 0 1px 2px rgba(20, 24, 40, .04), 0 8px 24px rgba(20, 24, 40, .06);--maxw: 1140px;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Roboto,Helvetica,Arial,sans-serif}@media (prefers-color-scheme: dark){:root{--bg: #0e1017;--surface: #171a24;--border: #262a37;--text: #e8eaf1;--muted: #9aa1b2;--brand: #818cf8;--brand-soft: #1e2033;--brand-ink: #c7d2fe;--shadow: 0 1px 2px rgba(0,0,0,.3), 0 8px 24px rgba(0,0,0,.4)}}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);line-height:1.6;-webkit-font-smoothing:antialiased}a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}.wrap{max-width:var(--maxw);margin:0 auto;padding:0 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