<!DOCTYPE html> <html> <head> <style> optgroup {color: red} optgroup:disabled {color: green} optgroup[disabled]:disabled + optgroup {color: green} optgroup:not(:disabled) {color: red} </style> </head> <body onload='document.getElementById("ogone").setAttribute("disabled", "disabled");'> <select size="2"> <optgroup id="ogone" label="There should be no red"> </optgroup> <optgroup id="ogtwo" label="There should be no red"> </optgroup> </select> </body> </html>