Inputs are formatted not following the W3 box model convention in different browsers, you might want to include:
input /*Content follows box model*/
{
-moz-box-sizing: content-box;
-webkit-box-sizing: content-box;
box-sizing: content-box;
height:24px;
}
Also include for firefox (which Shelly pointed out):
input::-moz-focus-inner /*Remove button padding in FF*/
{
border: 0;
padding: 0;
}
Otherwise you could use button
I collected all these solutions from various sources, they deserve the credit