body {
    margin: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

#nav-box {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    grid-gap: 20px;
    padding: 20px;
    background-color: #f1f1f1;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.model-btn {
    font-size: 300%;
    display: block;
    padding: 10px;
    background-color: #4CAF50;
    color: white;
    text-align: center;
    text-decoration: none;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.model-btn:hover {
    background-color: #45a049;
}