body {
    background-color: #f8f9fa;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}
.container {
    text-align: center;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
.btn {
    margin-top: 20px;
    padding: 10px 20px;
    font-size: 1.2rem;
}
footer {
    text-align: center;
    margin-top: auto;
    padding: 10px 0;
    width: 100%;
    background-color: #f8f9fa;
    border-top: 1px solid #ddd;
}