Inspect Element in Safari? I've tried Firebug Lite for Safari, but content wasn't editable. Is there an alternative to edit HTML, CSS, etc?
Just enable Show Developer Menu in Safari's Preferences, Advanced tab.



It will enable the option Inspect Element when you right click the page. You can also start it with Command+Option+I.

You can get more info about this option in Safari for Developers - Tools and Safari Web Inspector Guide: The Develop Menu.