Glad to hear you are still loving the site….as for your question, I am assuming you are needing more room for your main menu so it doesn’t go to a second line?
The only way to change this is to use a child theme (which this theme has one in a folder “child-theme” that you can install and activate. However, you would need to redo your widgets, menu, and any theme options because WP will see this as a new theme activation. But, with a child theme, you can copy the header.php file from Circumference Lite into the child theme, then open it, change two container classes, and you’re done.
You would look for this:
<div class="col-md-5">
and change the class to col-md-4 so it takes some width off the logo container and allow more room for the nav container to be wider (next to it). The nav class looks like this:
<div class="col-md-7">
So you would make the class as col-md-8 and then you will have a bit more room for your menu.
The benefit of using a child theme to make theme file changes like this, is that whenever there is an update for Circumference Lite, you won’t lose your modifications.
