.rainbow-button{position:relative;color:#fff;font-weight:600;cursor:pointer;border-radius:5px;text-shadow:1px 1px 1px rgba(0,0,0,.5);background:none}.rainbow-button:before{position:absolute;content:"";height:100%;width:100%;border-radius:5px;z-index:-1;opacity:1;filter:blur(3px);background:linear-gradient(45deg,red,#ff7300,#fffb00,#48ff00,#00ffd5,#002bff,#7a00ff,#ff00c8,red);background-size:400%;transition:opacity .3s ease-in-out;animation:animate 20s linear infinite}.rainbow-button:hover:active:before{filter:blur(2px)}@keyframes animate{0%{background-position:0 0}50%{background-position:400% 0}to{background-position:0 0}}