In the previous section, you saw how you could manage and modify SharePoint CSS styles using SharePoint Designer. However, there are several browser tools that you will find invaluable when styling and customizing SharePoint sites, specifically the Internet Explorer Developer Toolbar and Firefox’s Firebug.
Internet Explorer Developer Tools are built-in starting with Internet Explorer version 8. You need to separately download the developer toolbar for Internet Explorer 7 from the following location:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=95e06cbe-4940-4218-b75d-b8856fced535. In addition, you need to download Firebug separately for Firefox from https://addons.mozilla.org/en-US/firefox/addon/firebug/ ...