Code:
#productGeneral {position: relative;}
#cartAdd.box-1 {
position: absolute;
top: 331px;
left: 154px;
}
#cartAdd.box-1 input {
position: relative;
top: 6px;
}
Positioning relative to an element dozens of lines down the page from the desired location is risky. Absolute positioning from the top of the container leaves less room for browser rendering differences to creep in.
On another subject, I see you have something that names and positions attributes individually. It's not Flexible Attributes; what is it and where did it come from? Just curious.