body {
background-color: #2c3e50;
color: white;
font-family: 'Arial', sans-serif;
display: flex;
justify-content: center;
align-items: center;
height: 100vh;
margin: 0;
}
.card {
background: #34495e;
padding: 40px;
border-radius: 15px;
box-shadow: 0 10px 20px rgba(0,0,0,0.3);
text-align: center;
max-width: 400px;
}
button {
background: #2ecc71;
color: white;
border: none;
padding: 10px 20px;
border-radius: 5px;
cursor: pointer;
margin-top: 20px;
}