html, body {
    height: 100%;
    margin: 0;
    font-family: Arial, sans-serif;
}

body {
    display: flex;
    flex-direction: column;
}

header {
    background: #2c3e50;
    color: white;
    padding: 15px;
    text-align: center;
}

main {
    flex: 1;
    padding: 20px;
}

footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 10px;
}