Firefox v IE margin problem

[Mancotter]

I have modified a phpbb template and added a style sheet to place my own banner and navigation bar above the original container.

It all looks fine in ie, but in Firefox and Safari the original container is extended upwards so that it covers most of my banner and nav bar. The divs within the container are appearing below my nav bar - which is where I want them to be.

Can anyone suggest why, in Firefox and Safari, my own divs are failing to 'push' the original container down?

Thanks

[milosevic]

Hi Mancotter and welcome to Webmasterworld!

If you can post some HTML and CSS it will make it much easier for us to diagnose a possible problem.

One thing I will say

It all looks fine in ie, but in Firefox and Safari

Develop for standards compliant browsers, and then fix for IE, not the other way round - it's simple to use conditional comments to fix IE based problems (but there's no equivalent for other browsers) and working out what is wrong is far more logical when you know you are working from the HTML/CSS standard.

[Mancotter]

Solved it with an inline style! The problem was the top margin on the existing phpbb wrapper.
Thanks milosevic, I take your point about developing for Firefox first.