It’s because your image is too wide. All genesis themes show header images like this. In order for it not to cut off, you would either need to have another smaller image that loads when viewed on mobile devices….or you’ll need to add some css that will make it adjust to the width of the browser. Background images by default are not responsive. Inline images are, but background images are not.
You’ll have to figure out which way you would like to go about handling this, but if you choose the responsive way your image will shrink to a small size to fit the mobile screens size. You could try adding something like – background-size: contain !important; to your #header in the responsive section of your css, but it may not look right due to the size of your image. Your image probably won’t look right scaled down to a small browser, but you can give it a try.
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