a.button4{
 display:inline-block;
 padding:0.3em 1.2em;
 margin:0 0.1em 0.1em 0;
 border:0.16em solid rgba(255,255,255,0);
 border-radius:2em;
 box-sizing: border-box;
 text-decoration:none;
 font-family:'Roboto',sans-serif;
 font-weight:300;
 color:#FFFFFF;
 text-shadow: 0 0.04em 0.04em rgba(0,0,0,0.35);
 text-align:center;
 transition: all 0.2s;
}
a.button4:hover{
 border-color: rgba(255,255,255,1);
}
@media all and (max-width:30em){
 a.button4{
  display:block;
  margin:0.2em auto;
 }
}