Hello o/ (it is late, I know ^^')
How can you aligned the tiles ? (is it not automatic with unity ?)
I fine :) a little tired because I finish my game for gamejam without sleep (2 nights ^^"). But now, it is finish :p.
Congratulations on finishing the game for game jam XD I'm glad you finished it so now, you can take a rest after a long time hardwork. XD
I think one of the way to do it is via Unity Tilemap.
https://learn.unity.com/tutorial/introduction-to-tilemaps#
https://docs.unity3d.com/Manual/class-Tilemap.html
That way the ground is placed on tile with same size, and aligned within grid.