@keyframes b{
0% {color: #FF0000;}
12.5% {color: #FF7F00}
25% {color: FFFF00;}
37.5% {color: #00FF00;}
50% {color: #0000FF;}
62.5% {color: #480082;}
75% {color: #8F00FF;}
100% {color: #FF0000;}
}
b {
color: red;
font-size: 50px;
animation: b 0.5s infinite;
}
Rainbow!!!