button{font-size:18px;letter-spacing:2px;text-transform:uppercase;display:inline-block;text-align:center;font-weight:bold;padding:0.7em 2em;border:3px solid #97C00C;border-radius:2px;position:relative;box-shadow:0 2px 10px rgba(0,0,0,0.16),0 3px 6px rgba(0,0,0,0.1);color:#97C00C;text-decoration:none;transition:0.3s ease all;z-index:1}button:before{transition:0.5s all ease;position:absolute;top:0;left:50%;right:50%;bottom:0;opacity:0;content:'';background-color:#97C00C;z-index:-1}button:hover,button:focus{color:white}button:hover:before,button:focus:before{transition:0.5s all ease;left:0;right:0;opacity:1}button:active{transform:scale(0.9)}body{margin:0;height:100vh;