Text is easier to read if it does not extend across the entire width of a large screen. While you need not mandate text width, it is recommended that text block width be a maximum of 640 pixels. Avoid the use of all upper-case letters, even in titles. The official background colour for U of T at Scarborough Web pages is white. Text is easiest to read against solid backgrounds.
White backgrounds are the most readable, but very light colours can work well too.
Make sure the background and text have good contrast and colour compatibility with each other.