I had a beer fueled idea of staining my bathroom subway tile grout lines from white to charcoal, and initially used a pen, then a grout stain since it seemed easier. also used a sealant after. However, midway in the process I realized the contractor has laid the grout poorly with a lot of excess grout/splashes on tiles which became much more visible after staining. Now I have a large shower and floor with uneven dirty looking grout. I ll get a tile guy to come look at it but what could be a plausible solution? regrout, restain. can i DIY it still? is there a chemical stain remover available? ( I still like the look fwiw, from afar.. upclose it looks nasty)