h2.filter {
    text-align: center;
    font-size: 5rem;
    font-family: 'Courier New', Courier, monospace;
    animation-name: animate;
    animation-duration: 2s;
    animation-iteration-count: infinite;
    color: orangered;
    
}

@keyframes animate {
    from {
       filter: hue-rotate(0deg);
    }
    to {
       filter: hue-rotate(360deg);
    }
}