Why cannot people just assign the required width to the proper elements without polluting markup with those .grid_x classes is beyond me. One may just put some .top_left_red_link and .orange_button there as well then.

If you do it properly and want your .features element to take more space you just go to your CSS and adjust width: accordingly.

If you are using some "grid system", then you go to your markup and change .grid_2 to .grid_4. And when you change markup to change presentation instead of modifying CSS—you are doing something wrong.