.custom-header {
  height: 20vh;
  
}

@supports ( object-fit: cover ) {
.has-header-image:not(.twentyseventeen-front-page):not(.home) .custom-header-media img {
height: 100%;
left: 0;
-o-object-fit: cover;
object-fit: cover;
top: 0;
object-position: 0% 0%;
-ms-transform: none;
-moz-transform: none;
-webkit-transform: none;
transform: none;
width: 100%;
}
}