:root{color:#0f2c59;background:#f0f7ff;font-family:Arial,sans-serif}body{margin:0}main{background:#fff;border-radius:16px;max-width:720px;margin:4rem auto;padding:2rem}h1{margin-top:0}button{color:#fff;cursor:pointer;background:#2a95f2;border:0;border-radius:8px;padding:.75rem 1.2rem}ul{line-height:1.8}.warning{color:#a52020}