Board Thread:Support Requests - Getting Technical/@comment-25263848-20140828151732

I want to create a "themed" button e.g the "post" button bellow, or join chat, that reflect the currently selected theme.

Is there any class that can be safely used, that will apply the theme css style? (like color1 and color2 that apply the theme designer chosen color) or should I manually copy and adjust the css code when necessary is the only way? 