.button1{position:relative;background-color:#00009c;color:#fff;padding:12px 24px;border-radius:8px;overflow:hidden;z-index:1}.button1::before{content:"";position:absolute;top:0;left:0;height:100%;width:0;background-color:#fc4191;z-index:0;transition:width .5s ease}.button1:hover::before{width:100%}.button1 *{position:relative;z-index:1}