You have two (actually three) problems.
1. You don't specify your units:
l5.Style["Top"] = "1361px";
or em or whatever
2. You need to set the position
labelId.Style["position"] = "relative";
where
labelId
= l, l5 etc. and
relative
is my best guess at the type of CSS positioning you want, YMMV.
3. Some of the co-ordinate numbers you are using are huge for a web page. A
left
of 8161px would imply your page is roughly more more than four screens wide for most users. I assume you are using these values to test, but there is a danger you will miss these labels when testing as they are so far off the screen without scrolling.