var selectWidth = parseInt(selects[q].className.replace(/width_/g, "")); center.style.width = selectWidth - 10 + 'px'; selectArea.style.width = selectWidth + selectRightSideWidth + selectLeftSideWidth + 'px'; button.style.width = selectWidth + selectRightSideWidth + selectLeftSideWidth + 'px'; button.style.marginLeft = - selectWidth - selectLeftSideWidth + 'px'; Code (markup): The second line is giving an invalid argument error in IE. How can I fix that? Thanks in advance, Tim