Image header responive problem

Hi, the header image is designed to cover the viewport.

Find this part in functions.php, line 298:

.site-header {
background: url(<?php header_image(); ?>) no-repeat center center;
-webkit-background-size: cover;
-moz-background-size:    cover;
-o-background-size:      cover;
background-size:         cover;
}

And replace center or cover with your preferred position.

Hi and thanks for to reply,

sorry but I did not understand, if I move the image becomes unresponsive for phones and tablets

I added

no-repeat center center fixed;

It has improved considerably

Great!