body {
    background-color: #e9ecef; /* Màu nền xám nhạt */
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.card {
    border: none;
    border-radius: 15px;
}

.btn-primary {
    background-color: #007bff;
    border: none;
}

    .btn-primary:hover {
        background-color: #0056b3;
    }

.btn-danger {
    background-color: #dc3545;
    border: none;
}

    .btn-danger:hover {
        background-color: #c82333;
    }

#result.alert-success {
    background-color: #d4edda;
    border-color: #c3e6cb;
    color: #155724;
}

#result.alert-danger {
    background-color: #f8d7da;
    border-color: #f5c6cb;
    color: #721c24;
}

footer {
    margin-top: auto; /* Đẩy footer xuống dưới cùng */
}