What does default CSS's browsers depend on?

Question

Hi (please excuse me for my ugly english ;-) )

Do you know if the default CSS of any user agent ... :

• depends on its release number ?
• depends on its layout engine ?
• depends on the release number of its layout engine ?
• depends on the OS ?
• depends on the OS release number ?

If yes (for any choice), have you any example do demonstrate it ?

Thank you very much. :-)

Answer 1

It only depends on the browser make/version. You can find here an overview of default styles.

The main differences are in the margins of the block elements. One would recommend to use a CSS reset sheet to clean it up, but I'd just specify the margin for every actually-to-be-used block element yourself.

Answer 2

It depends on the rendering engine used by the browser.

Answer 3

Unless you specifically need to know the defaults properties for your project - I'd recommend looking into using a 'reset script'.

If you use such a script, it will standardise the CSS defaults so they're the same across a range of browsers. Yahoo produce a good one, which is updated with each browser release (http://developer.yahoo.com/yui/reset/)