The visual style was enjoyable. Mechanically, I found it a bit tough to connect with though. Some feelings:
Some easy changes: - The "START" button really doesn't need to be a button at all. Clicking anywhere should be sufficient. The mouse hovering the button doesn't imply it's a button so no reason to add confusion. I must have clicked it by accident the first time, because on my second run I had no clue how to start!
- The SCORE at the end of my game was always 0, even if it was incrementing during the game.
- After dying, I'd want the game to reset on button press / click instead of waiting 4 seconds. That 4 seconds is unplayable and unfun time! Give the player control :)
Some harder changes: - Running "backward" felt very difficult and heavy. Consider making that feel more natural. I don't enjoy the feeling of not being in control of the player character.
- The block placement mechanic did feel quite right. For it be useful as a platform, you'd pretty much have to click exactly on the player character which doesn't seem to be the fun part of the mechanic. I'd frequently wiff past the block even when it was positioned pretty well. Maybe a button to spawn the block underneath the player and stop momentum could solve that... it really depends what the goal of the block-building is.
- I wasn't able to successfully interact with the red block due to frustration of the above issues. If I could reset the game faster, I'd probably give it a few more goes.