Are a blogger? Or,..webs administrator? Of course you know this tool already. Firebug,..an addon of your browser. Yes,..you'll get alot of advantages from this tool. You may edit, debug and monitor of CSS, HTML even JavaScripit in any web page that you curious in.
Sometimes you just want to know the code of the background, or the font color, or the font sizes,..firebug could do these, even you can edit directly, in colors, in font size of a web page you are visiting and the changing will appear directly, so you will know the best configurations should be, of course it's not really change the actual web page, instead the owners become angry rigth,... Just install to your browser, make a little experiments, then apply to your blogs or your webs what you get for "spying" any webs.
Here,.you should proceed to get it;
https://addons.mozilla.org/en-us/firefox/addon/firebug/
Or
http://getfirebug.com/
