Just a caution here. You mentioned that you want a mold/fungus resistant caulk.
The manufacturers add fungicide to white caulk, and probably other colors. Brands like Quick Seal stay white for years, because they are so high in fungicides. Latex caulk of other brands might have fungicide, too.
Pure Silicone resin in calking tubes can't ever support the growth of anything. But, it only sticks well to smooth surfaces like glass, tile, formica, or glossy painted surfaces, clear acrylic and polycarbonate. And others. Note that it is extremely adhesive to the proper surfaces. Once applied, it is nearly impossible to remove.
Before applying clear Silicone
Resin, paint the areas you are going to caulk with a couple of layers of clear shellac (because it dries quickly). That finish should allow Silicone to seal strongly to it. Polyurethane would make a better surface for you, but it takes 4 to 24 hours to dry.
I know this information because I've remodeled nearly 100 bathrooms in California over the last 40 years. I've use the right caulk and used the wrong caulk. Silicon resin is the only caulk that will stick well to cured silicone caulk.