:root{color-scheme:light dark;font-family:system-ui,-apple-system,Segoe UI,Roboto,PingFang SC,Microsoft YaHei,sans-serif}*{box-sizing:border-box}body{margin:0;min-height:100vh;display:grid;place-items:center;background:linear-gradient(135deg,#1e3a8a,#0ea5e9);color:#f8fafc}main{text-align:center;padding:2.5rem 3rem;background:#0f172a59;border:1px solid rgba(255,255,255,.15);border-radius:1.25rem;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);max-width:32rem}h1{font-size:1.8rem;margin:0 0 .75rem}p{line-height:1.6;opacity:.92}.sub{font-size:.9rem;opacity:.75}button{margin-top:1.25rem;padding:.7rem 1.4rem;font-size:1rem;font-weight:600;color:#0f172a;background:#f8fafc;border:none;border-radius:.6rem;cursor:pointer;transition:transform .08s ease}button:active{transform:scale(.96)}