I’m not sure if its WP or GT causing this issue. But in Posts I add my own code in Text mode like for example:
<p><button style="background-color: red; color: #ffffff; font: 11px Arial;"> Adobe PDF </button></p>
then I change to Visual Mode and Button has red Background with White font Color. But When I preview its Blue Background with white text.
So all my buttons from previous posts are blue with white fonts. So the button code above is not working anymore. Must be some default setting somewhere. Does samething in twenty theme also. Thank You