Background Color

– Try using, for example, a tool like Firefox with the Firebug add-on for this kind of CSS work. https://getfirebug.com/ . Help info on Firebug https://getfirebug.com/faq/
– Newer IE and Chrome also have similar tools
– Also, check this plugin: https://www.ads-software.com/plugins/custom-css-manager-plugin/

I’ll give them a try. Thank you.