body{margin:0;font-family:Arial,sans-serif;background:linear-gradient(135deg,#ff8a00,#2ec4b6);min-height:100vh;display:flex;justify-content:center;align-items:center}.container{background:#fff;padding:2rem;border-radius:16px;box-shadow:0 10px 30px rgba(0,0,0,.2);width:320px;text-align:center}h1{color:#ff8a00}input,button{width:100%;padding:12px;box-sizing:border-box;margin-top:10px;border-radius:8px}input{border:2px solid #2ec4b6}button{border:none;background:#2ec4b6;color:#fff;font-weight:bold;cursor:pointer}button:hover{background:#26aa9d}#error{color:red}