The following code appears to be auto-populated based on values on the Appearance tab of the Corporate Clean theme. However, this line of CSS is problematic if the user selects a three digit (i.e., #FFF) hex code as opposed to the full hex code (i.e., #FFFFFF) as a color:

filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff', endColorstr='#fff');

IE cannot properly render a three digit hex code using this command, and will render different values on the actual page. This issue does not persist for Chrome, Safari, or Firefox.