Male Fashion Advice

The other day I saw a guy wearing pants that look like they had a chino cut. They had a distinct design detail which was that the fabric clasp that closed one of the back pockets was in neon pink. The fabric might have been cotton, but could also be some kind of mixed technical fabric. I couldn't tell. The pants were dark navy colour, almost black.

The pants also had the same neon pink inseam detail, which was visible because the person had their pant leg rolled up once or twice. It showed similar to the red lines on a pair of selvedge denim pants.

I noticed that the other back pocket seemed to have a zipper closure.

The guy was in front of me on a bike, and I didn't manage to get his attention to ask him where he had bought his pants.

So now I'm asking in the lemmyverse, any sartorialists out there who has seen these pants, and know what make they are? I tried Googling, but it didn't return that particular brand.