Before you go scrubbing like a maniac, do a tiny test on an inside seam. Nobody wants a faded patch on their elbow. Dip a cotton swab in your cleaning solution (water + a drop of gentle dish soap) and dab the hidden spot.
If the color stays put and you don’t hear a tiny scream, you’re golden. If it does change color, panicking is acceptable, but only for five seconds. Then adjust your plan.