Cthulhu1976 on "[Theme: Mantra] My Custom Header Image Isn't Responsive?"

Hi guys,

just had a quick look at carapacebooks.co.uk.

If it's urgent, you might want to edit your style.css:
Look for the following sections: #branding and #bg_image:

Switch from:

#branding {
height: 200px;
}

to:

#branding {
height: 100%;
}

And also edit the following from:

#bg_image {
display: block;
margin: 0 auto;
}

to:

#bg_image {
display: block;
margin: 0 auto;
max-width: 100%;
}

The bg_image's max-width in combination with the 100% height of #branding is what does the (responsive) magic :).

Anyway: Please keep in mind that if you use the theme as is and not as a child theme, the next update of this theme might (or certainly will) overwrite these values again.
If you need a quick fix for the current status, you might give it a shot with the two code additions I mentioned.

Hope this is of help?