:root{--ink:#17293b;--ink-soft:#46586b;--muted:#7b8a99;--accent:#0f766e;--accent-dark:#115e59;--accent-soft:#e6f4f2;--bg:#f5f8fa;--card:#ffffff;--line:#dfe7ee;--radius:14px}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Noto Sans SC,sans-serif;background:var(--bg);color:var(--ink);line-height:1.7}a{color:var(--accent);text-decoration:none}a:hover{color:var(--accent-dark)}.container{max-width:1080px;margin:0 auto;padding:0 20px}.site-header{position:-webkit-sticky;position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}.header-inner{display:flex;align-items:center;justify-content:space-between;gap:16px;min-height:60px;flex-wrap:wrap;padding-top:6px;padding-bottom:6px}.brand{display:flex;align-items:baseline;gap:8px}.brand,.brand:hover{color:var(--ink)}.brand-mark{color:var(--accent);font-weight:700;font-size:18px}.brand-name{font-size:20px;font-weight:800;letter-spacing:.5px}.brand-sub{font-size:12px;color:var(--muted)}.main-nav{display:flex;gap:4px;flex-wrap:wrap}.main-nav a{padding:6px 12px;border-radius:999px;color:var(--ink-soft);font-size:14.5px}.main-nav a:hover,.nav-search{background:var(--accent-soft);color:var(--accent-dark)}.nav-search{font-weight:600}.hero{padding:60px 20px 36px;text-align:center}.hero h1{font-size:clamp(30px,5vw,44px);margin:0 0 12px;letter-spacing:1px}.hero-dot{color:var(--accent)}.hero-desc{max-width:640px;margin:0 auto 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