Divs Won't Resize For A Width Of Less Than 420px

I'm having a little problem with the auto-resizing feature! I've already proficiently triple-checked (with the search-tool) that all my width-settings are set to %. There's nothing

Solution 1:

I think I resloved problem with Firefox. I think FF allows to shrink website to minimal width which need toolbar with website address, searcher, bookmarks and so on. I was testing on CSS tricks which is great site if comes to mobiles :)

At the first screen at 280px width toolbar stops shrinking as the website. Sometimes I have there also Firebug icon or Fireftp icon which makes my sites stop shrinking earlier.

But right click on toolbar and unchecked Toolbar menu. Menu should hide and site still shrinking on resize. Here is Firefox and Chrome and as you can see they are quite similar as comes to minimal width.

If anyone will notice that this soultion is wrong and didn't work, please give me a feedback :)