For any site:

1) Press the "Ctrl" Key on your keyboard
2) After which turn the mouse wheel to increase and decrease text size.

Try out an anti glare screen on for your computer monitor so your able to visit and read more of the sites you want to, and as it will work better even if colours, by each user, can be custom set because not every combination which may be desired can be known in advance to build this in and they are near enough infinate, as the combinations can run in to millions, and still may not work as fully as it could be.

You can read more on text size changing here

I hope this helps

KR