spanning cells interfere with the td:nth-child(even) logic

Im trying to build a timetable that includes a vertical cell-spans because u-know-why, but the (intentionally)missing cells are not counted in my :nth-child(even) - rule, which bugs the visual display of the table. To further elaborate, pay close attention to the third cell right of the spanned cell:

http://jsfiddle.net/WbtvT/

Is there any way to mak开发者_开发问答e the css count the missing(spanned) cells as well? Or maybe some jquery magic?

There is no flexible solution here. You have to hardcode the box you want to shade yourself, if that is acceptable?

.shade {background-color:silver;} Add this line in CSS

Ass the TD that is going to be affected the class="shade"

Do you want a flexible solution? What is your criteria

Here is jfiddle