Colours can be altered in look and layout.
Click on profile and hover over modify profile and themes can be changed to suit you preference.
If larger text is required this can be done if you enlarge your browser interface, You will notice in th right hand bottom corber of your screen a box (generally above the clock) it shows a percentage view, generally preset at 100%, if you click it, it will enlarge your veiw but it will also limit your screen view, you can however just use your arrow keys to move the screen around or click again to reduce. Huub i think the above might be your problem.
Hope this helps.
Tom