:root{--bg: #f4f6fa;--card: #ffffff;--ink: #1d2733;--ink-soft: #5b6b7c;--primary: #2f5fce;--primary-dark: #1f4aa8;--accent: #f5a623;--red: #e0454e;--green: #2e9e6b;--line: #e3e8f0;--radius: 14px;--shadow: 0 2px 10px rgba(29, 39, 51, .06)}*{box-sizing:border-box}html,body{margin:0;padding:0}body{font-family:PingFang SC,Microsoft YaHei,Segoe UI,system-ui,sans-serif;background:var(--bg);color:var(--ink);-webkit-font-smoothing:antialiased}.app{min-height:100vh;display:flex;flex-direction:column}.main{flex:1;width:100%;max-width:960px;margin:0 auto;padding:20px 16px 80px}a{color:var(--primary);text-decoration:none}.header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}.header-inner{max-width:960px;margin:0 auto;padding:12px 16px;display:flex;align-items:center;gap:14px}.logo{font-weight:800;font-size:18px;letter-spacing:.3px;color:var(--ink);display:flex;align-items:center;gap:8px}.logo 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