We apologise for the late review:
Unfortunately, your game only shows properly in the browser if you maximize the browser via F11. The game runs smoothly and without a lot of lag which is nice. The camera movement with the mouse is a bit disorienting as it does not make sense with the chess-card battlefield layout. Upgrading yourself with the cards you pick up is really neat, but it can be hard to actually know if you've put the upgrade in the right place. This is made worse with the mouse causing the camera to also move with it, potentially obscuring the proper area to set a card to upgrade your character. This also includes attacking: it is hard to see where the enemy is to attack. The turns don't seem to have much effect, and the stats on the top left are difficult to see at a glance. I suggest making a UI element that is very distinguishable from the background so that the character stats are easier to see. I do like the art style and general game layout.
Your GDD is very bare bones and lacks the most basic of information regarding your game. The GDD is your guide to how you plan to make your game, so it should at least have the basics in it. For future work on this game, I suggest you fill out the GDD and include all the relevant information regarding everything you need to move forward in development of the game. I also suggest that any future game dev projects you go for also start with a GDD before any development happens.
I do hope you continue development with this game and finish it. Have fun and make games!