a.button4{
margin: 10px;
font-family: "Arial Black", Gadget, sans-serif;
font-size: 30px;

display:inline-block;
padding:0.3em 1.2em;
border:0.16em solid rgba(255,255,255,0);
border-radius:2em;
box-sizing: border-box;
text-decoration:none;
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;
}
}