.submit-btn {
    background-color: #4CAF50;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;

        padding: 15px 30px;
        font-size: 18px;
        font-weight: bold;
        text-transform: uppercase;
        border: none;
        cursor: pointer;
        background: linear-gradient(90deg, red, orange, yellow, green, blue, indigo, violet);
        background-size: 400%;
        color: #fff;
        border-radius: 8px;
        animation: gradient 3s infinite;
}