Background color in a table

I’m wanting a color background for a table within a post. The color shows up in the WP editor, but not in the browser (IE and Chrome). I’ve tried entering the background attribute in all the elements of the table, but no solution. I’m thinking the theme is overriding the HTML tag, but I don’t know enough about CSS to find where that happens. I’ve made a child theme and could add what’s needed there, if I knew what it was. Any suggestions would be appreciated.