Removing a border at the very bottom of Handy theme header is problematic for some of our clients and needs certain clarification.
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Removing it is quite simple. You need to add the following CSS code to Appearance -> Customize -> Additional CSS:
/* Remove border bottom of the header */ .header-primary-nav { box-shadow: none; -webkit-box-shadow: none; }
Save changes and refresh your home page, the border should be gone.