body{font-family:system-ui,sans-serif;margin:0;background:#f5f7fa;color:#222;text-align:center}
header{background:#4f46e5;color:#fff;padding:3rem 1rem}
main{padding:2rem}
button{background:#4f46e5;color:#fff;border:0;padding:.7rem 1.4rem;border-radius:8px;font-size:1rem;cursor:pointer}
button:hover{background:#4338ca}