You can use Grading Colour Codes to apply background and text colour to items in the Grade Centre that meet specified criteria.
Adding colour rules to the Grade Centre provides visual indicators to help you interpret information quickly.
Open the Full Grade Centre from the Grade Centre section of the Control Panel:

Click on the drop down arrow next to the Manage button, and select Grading Colour Codes:

Colour coding is not available by default.  To enable this feature, check the Enable Grading Colour Codes box:

Colours can be defined for items that are in progress, items that need grading or items that are exempt.  Choose a background colour for each grading status by clicking on the appropriate chevron and selecting a colour from the colour swatch box:

It is also possible to set colour options for different grade ranges by clicking on the Add Criteria button in the Grade Ranges section:

Adding criteria to grade ranges makes it easier to set up your own system of visual recognition.  For example, you can use red to highlight low grades that need attention.  It is also possible to change the colour of the text to make it readable against the background you have selected.
When you have finished your changes, click on the submit button.
Your colour coding will then be applied to the Grade Centre.