Problem with CSS files?

Hello everyone, I have some problems
The first, I use FF5 and IE7 open my page, but different result when it is opened with FF5 or IE7
[B]Picture1 about buttons’ Width[/B]
[B]Pictiure2 about Textbox[/B]
and they are css files. I use two css files in my page

Help me. Thanks your helps very much