The Underscore Hack
The underscore hack is particularly useful if you only have a few minor things that need adjustments. It’s also useful since you can keep your IE CSS with the real CSS, making it easier for adjustments down the road. Now you’re probably wondering how the underscore hack works.
Let’s say you a class called text, and you want to apply a 10 pixel margin to that text. The 10 pixel margin looks great in every browser but IE. To make IE look better you think it needs a 15 pixel margin. To accomplish that you need to give IE code that only it will understand. This can be done by the following code:
This hack works because IE is stupid. An underscore in CSS acts as a comment for that attribute only, and all browsers but IE honor this. Since IE doesn’t follow the underscore rule, placing the same attribute with an underscore after the real attribute will redefine that attribute for IE, while all other browsers will skip the second redefined attribute. Ah, using IE’s stupidity to solve IE stupidity. Brilliant!