So, I thought that I would have a go at converting a site from all px to em to help with accessibility and using browser zoom. I wish I'd never started!
This is how I approached it.
1) Set my font to 100%
2) Change all font sizes to em
3) Feel smug
4) Notice that after a couple of ramps up on the zoom the layout goes pear-shaped
5) Change all width/height dimensions to em
6) Change all padding/margin dimensions to em
7) Feel a little tearful
8) Realise I don't have a back-up style sheet
9) Re-draw WWW domination plan
10) Start to make a little progress
11) Try out the negative zoom
12) See that screw my layout - don't understand it
14) Add some min-width/min-height rules
12) Feel a little tearful...
13) Came here to be with friends
I worked out I think, that using flexible units in a fixed environment is going to cause problems.
I'm having trouble with layout more than text-size. I think the only thing that will cause me grief with text-size is with nested element and the way that em is inherited but, the site is quite straight forward, apart from a few floated elements.
I thnk my main problems are with the layout: Images, background images and how to approach the whold width/height thing.
PS I won't be at my PC for a while so, if you respond and I don't come back to you, it's not because I'm not interested. I'm too ashamed and confused to post a live page!