You can also try transform
property:
.wrapper h4 {
margin-top: 0;
position: relative;
text-align: center;
top: 50%;
transform: translateY(-50%);
-webkit-transform: translateY(-50%);
-o-transform: translateY(-50%);
-moz-transform: translateY(-50%);
-ms-transform: translateY(-50%);
}