Using IE v.10:

I append a class to an input text control, and suddenly notice that it's upper and lower padding had increased from 1px to 2px (evident in the F12 debugger).

When the class that I am appending defines a background-color, the side-borders' widths are also increased from 1px to 2px.

What up with that?

Strange that I haven't noticed it before...

Yes, I know that I can define the borders statically, and am simply wondering about this odd behavior. Anyone know what it is in the browser's binary code that's causing it?