:root{color-scheme:light dark;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,sans-serif}*{box-sizing:border-box}body{margin:0;min-height:100vh;background:#f8fafc;color:#0f172a}.container{max-width:840px;margin:0 auto;padding:3rem 1.25rem}button{border:1px solid #334155;border-radius:8px;background:#0f172a;color:#fff;padding:.6rem .9rem;cursor:pointer}button:hover{opacity:.9}