Updated answer
Here is how to change the box model used by the input/textarea/select elements so that they all behave the same way. You need to use the box-sizing
property which is implemented with a prefix for each browser
-ms-box-sizing:content-box;
-moz-box-sizing:content-box;
-webkit-box-sizing:content-box;
box-sizing:content-box;
This means that the 2px difference we mentioned earlier does not exist..
example at http://www.jsfiddle.net/gaby/WaxTS/5/
note: On IE it works from version 8 and upwards..
Original
if you reset their borders then the select
element will always be 2 pixels less than the input
elements..