Explorer, Safari and Firefox
Each of the web browsers has a slightly different way of implementing the HTML standards. The differences are sublte, and annoying. As a web designer you have to work with it and do the best you can. What is the best way to make your web pages look good no matter what the browser?
My general approach is to write for the standards and ignore the non-standard implementations in browsers like the (now obsolete) Explorer 6. It's up to them to fix the browsers to work correctly, and I'm not going to tie myself in knots trying to fix their mistakes.
But, if you are writing for a customer, they may not be satisfied with this approach. And the customer is always right.
So yes, you can use CSS to modify your pages so that they look the same in each browser.
The following article explains a general method for writing CSS rules that apply only to one type of browser:
http://webdesign.about.com/od/internetexplorer/a/aa082906.htm.
The main problem is that this article doesn't give the specifics of what you might actually need to do, it only shows how to detect the browser type.
Here are some really complicated "hacks" that will detect browser types:
http://www.nealgrosskopf.com/tech/thread.php?pid=20
Here is a Wikipedia article that discusses the same issues. It's actually a little more clear in explaining the hacks.
http://en.wikipedia.org/wiki/CSS_filter
This page gives a list of websites that will allow you to test your website under different (simulated) browsers. This will be very useful in detecting problems.
http://www.digitalfamily.com/dreamweaver/resources/web-browser-test.html
The nice folks at W3Schools have a css tester that can be very useful:
http://jigsaw.w3.org/css-validator/
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