:root{--red: #e53935;--red-bg: rgba(229, 57, 53, .12);--yellow: #fbc02d;--yellow-bg: rgba(251, 192, 45, .12);--gray: #9e9e9e;--gray-bg: rgba(158, 158, 158, .12);--bg: #1a1a2e;--card: #16213e;--card-hover: #1a2a4a;--text: #e0e0e0;--text-dim: #9e9e9e;--white: #ffffff;--green: #4caf50;--green-bg: rgba(76, 175, 80, .12);--border: #2a2a4a;--font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;--radius: 8px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:var(--font);background:var(--bg);color:var(--text);font-size:16px;line-height:1.7;min-height:100vh}a{color:var(--yellow);text-decoration:none}a:hover{text-decoration:underline}.top-nav{position:sticky;top:0;z-index:100;background:#0f0f23;border-bottom:1px solid var(--border);padding:0 20px;display:flex;align-items:center;gap:4px;overflow-x:auto}.nav-item{padding:14px 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