Working JSFiddle, though I don't know if this solution is useful to you.
I set the #inner wrapper to top: 50%;
as well as setting position:relative
for the #text, then displacing it by top:-8px
(half of the font height of 16px).
There might be a better solution, but vertical centering has rarely a clean solution.
Edit: Updated JSFiddle showing the difference between my solution and the above one. Resize the preview window to see what I mean.