Conditional Comments!
IE7 isnt the worst ever, at least they have given us a way to declare specific IE stylesheets with the use of Conditional Comments. These are great little snippets of code, that allow IE to read between the comments and load a specific IE stylesheet.
Conditional Comments allow you to create a comment that only IE will read, while other browsers will simply skim over it. You can include a link to a stylesheet that declares CSS styles specifically to use with IE browsers.
Here is an example of how you can declare a stylesheet that only IE7 will see/read:
<!--[if IE 7]><link rel="stylesheet" type="text/css" href="IE7styles.css" /><![endif]-->
