body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #f5f5f5;
}

.container {
    text-align: center;
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

h1 {
    margin-bottom: 20px;
    font-size: 24px;
    color: #333;
}

button {
    font-size: 16px;
    padding: 10px 20px;
    margin: 10px;
    border: none;
    border-radius: 5px;
    background-color: #007bff;
    color: #fff;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #0056b3;
}

button.skinfold {
    background-color: #28a745;
}

button.bioelectrical {
    background-color: #dc3545;
}

button.dual-energy-xray {
    background-color: #ffc107;
}

button.hydrostatic {
    background-color: #17a2b8;
}

button.air-disp {
    background-color: #007bff;
}

button.body-scanning {
    background-color: #6f42c1;
}

button.boday-mass-index {
    background-color: #fd7e14;
}