Thank you for playing and for criticism, all very fair!
I didn't intend the game to start on the S button, originally the level starts once you move, but for some reason, despite its working fine in Unity Play mode, when I played in WebGl, the screen for some reason faded away immediately after starting the level, so I had to rush this solution before submition period was over.
And you right about the Restart button, I think I made that way because I wanted to make "one life" kind of thing, but I can see now that it's just frustrating instead.