This is an awesome prototype! I really feel like this is the perfect base for a full game, which could be an expansion of what is here. There a clear path for more complexity and/or difficulty. I did not find the demo difficult at all, so maybe future developments could ramp it up? Maybe the demo could be the tutorial/initial phase, as it explains the mechanics well and it's not hard. Great work! I love it!
I particularly like the art and character design. It's so charming and it all ties so well with the theme of tarot cards. Visually and stylistically, it's all done so well. Mechanically too, clearly, with the above note of the difficulty but it's definitely going in a good direction.
A minor thing that could be fixed is the position of the help windows when hovering over a UI element, as now it is partially obscured by the pointer. That is the only problem I encountered (I could still read 95% of the text, so it's not a huge deal but still a clear thing to fix).