Lycra comes in amazing colors and can be had at any big fabric store. It ain't cheap, but nothing compares, either.
Below is a piece of white lycra 60" wide I got wholesale from somewhere on the 'net. (The 30' diameter dome never got finished that year, but with guy ropes, it held together even in the big winds. The lycra stretched like crazy but for some reason didn't act like a sail and cause huge stress. It was more like a bowl being filled with water: more water in the already full bowl wouldn't change the pressure on the bowl! Amazingly, even after 3 years of stretching and playa dust (washing each year in those gigantic front loaders at some laundromats) there is very little "stretch-out" in the lycra.
Also, for all fabrics in uses like shade, use use marbles and pieces of strong small diameter rope, tying a clove hitch around the fabric that is covering the marble. Much better than gromets that can fail when they cut the material...also, the gromet doesn't distribute the stress as well as the "bunched" fabric. The marble and rope method is what's holding the stressed lycra on the dome: