You can change the background color of the header by adding something like this to your Custom CSS section –
.site-header {
background-color: #ff0000;
}
You can add custom CSS by going to “Appearance > Customize > Additional CSS” and copy/pasting the above code and then changing it to the color you want.
This method is recommended if you want to keep your custom CSS separate from the Theme files.
The other option is to edit the .site-header section of the CSS in the style.css file directly. I recommend using the 1st option of adding your own custom css to keep everything organized.
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