body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f9; /* Màu nền xám nhẹ */
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.container {
    background-color: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    text-align: center;
}

button {
    background-color: #28a745;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
}

button:hover {
    background-color: #218838;
}