#h2 {
    font-size: 3em;
    position: relative;
    animation: moveAndColor 10s infinite;
}

@keyframes moveAndColor {
    0% {
        left: 0;
        color:yellow;
    }
    50% {
        left: 50%;
        color: blue;
    }
    100% {
        left: 0;
        color:yellow;
    }
}