!important
Expression Studio 3.0
Increases the weight or importance of a particular declaration.
The following example includes an !important declaration in the style rule. Normally the color of the text would be red, because inline styles override the rules set in a style tag. By including the !important declaration in the style rule, you set the color of the content of the paragraph to green:
<style>
p {color:green!important}
</style>
<p style="color:red">This text will be green.</p>
This declaration is defined in Cascading Style Sheets (CSS), Level 1 (CSS1).