.btn{z-index:0;transition:all .3s ease-in-out;position:relative;overflow:hidden}.btn:before{content:"";z-index:-1;background-color:#fff;width:100%;height:0%;transition:all .5s ease-in-out;position:absolute;top:0;left:0}.btn:hover:before{height:100%;transition:all .2s ease-in-out}.btn-1{z-index:0;transition:all .3s ease-in-out;position:relative;overflow:hidden}.btn-1:before{content:"";z-index:-1;background-color:#0f0;width:100%;height:0%;transition:all .5s ease-in-out;position:absolute;top:0;left:0}.btn-1:hover:before{color:#151f27;height:100%;transition:all .2s ease-in-out}