To change the background color of a page, or the color of text and links for the entire page you will need to change default colors.

First, go to the menu item edit -> preferences
Then go to the Appearance category and double click on it.
To change the background color of your page, click on the subtopic “colors” Then, in the right hand side of the window, click on the colored square next to “background” a grid of palettes will appear, use your mouse to select the color you prefer.

To change the color of links, repeat the process. When you are finished modifying colors, click O.K.