CSS is not limited to .net, it is used for any HTML (or related) pages. CSS is used to create formating classes, these can be later used to format any web document object like - body, table, any paragraph etc.
You can use css on your webpage using -
1. inline style for example - <p style="font:10px Verdana; align:left">
2. create a text file and preferably name it .css, create formating classes like -
color : red;
border : 2 px ridge red;
and then use it on any object like a table division (td) as -
it will change the style of that table division ..
please read more about it here - http://www.w3schools.com/css/default.asp
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