Ranking system - how does it actually work?

Can anyone shed some light on how the ranking system works?

I’m fairly new to the game, but I went from Alchemist 6 -> Alchemist 3 just from one loss. Then I only rank up once on a win. (I still did the best on my team, with highest player damage most of my games).

My win rate is currently 56%.

Would love to have more insight into the rank/elo.

Thanks!