:root{--bg: #f6f7fb;--card: #ffffff;--ink: #101223;--muted: #6a7186;--brand: #4f46e5;--line: #e3e6ee;--shadow: 0 1px 2px rgba(16, 18, 35, .06), 0 6px 20px rgba(16, 18, 35, .06);color-scheme:light}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:18px/1.6 system-ui,-apple-system,Segoe UI,Roboto,sans-serif}.card{background:var(--card);border-radius:14px;box-shadow:var(--shadow);padding:24px}a{color:var(--brand)}h1,h2,h3{line-height:1.2}