.btn{position:relative;display:inline-block;background-color:#fff;border:none;cursor:pointer;overflow:hidden;transition:background-color .3s ease-in-out}.btn-2:before{content:"";background-color:#17004A;position:absolute;bottom:0;left:0;right:0;height:0;width:100%;transition:height .3s ease-out;border-radius:inherit;z-index:0}.btn-2 span{position:relative;z-index:10;transition:color .2s ease}.btn.hover-slide-up:hover:before{height:100%}.btn.hover-slide-up:hover span{color:#fff}