Do I assume you already found it? Not really an us thing, you might find it https://www.w3schools.com/css/default.asp or just google.
https://letmegooglethat.com/?q=rainbow+text+css copy and paste the code you find until you find one that works
.rainbow-text-animated { background-image: linear-gradient(to right, violet, indigo, blue, green, yellow, orange, red); -webkit-background-clip: text; -webkit-text-fill-color: transparent; animation: rainbow-animation 35s linear infinite; } @keyframes rainbow-animation { to { background-position: 4500vh; } } or this .rainbow-text-animated { background: linear-gradient(to right, violet, indigo, blue, green, yellow, orange, red); -webkit-background-clip: text; background-clip: text; color: transparent; animation: rainbow_animation 6s ease-in-out infinite; background-size: 400% 100%; } @keyframes rainbow_animation { 0%,100% { background-position: 0 0; } 50% { background-position: 100% 0; } } [3:43 PM] two different animations How do I make the an9imation work?
I don't think animation will work because the css is added to the style element of the html element, it's not it's own css sheet. But I'll have a look a little later.