Coloring Block Puzzle

This is "Coloring" Block Puzzle.
Take a relax with simple but challenging puzzle game.
There are No sudden pop-up video Ads :)
This game is not just a normal block puzzle.
It's a brand new block puzzle combined with coloring.

Rule is simple.
1. Fill the shape with given blocks.
2. Filled color must be the darkest color.
*You can make darker color by combining blocks.
*There are 3 color steps.