I can see where this game is going, and I really like the idea, having to create the different colours and put them into patterns is a really nice concept that makes sense. Unfortunately I don't think you executed the idea well in this.
The first thing, obviously you got the window size wrong and I had to zoom out to play.
I love the art style especially as you are going for printers so it makes sense to not me shiny metallic machinery. This is the aspect that worked the best. it's a shame you couldn't get and SFX in as some printer noises as items were grabbed and placed would have really brought it to life.
I know that you had a bunch of text explaining the game in the description, and it was quite detailed, but you needed something in the game as well. It does nothing to teach you how to play which is really unfortunate as having to keep scrolling down to read or look at screenshots was frustrating. it would be nice if there was a help button that would bring up tips or information when clicked. Also tooltips the pop up when the mouse hovers over items would be great. Visually I understood the conveyor belt but not the others.
Finally I think that it would be nice to be able to move things once they are placed down, or to be able to rotate them once they are placed. Maybe even just a few times like with an undo button. If this really breaks what you were going for then please put in a quick level restart button like 'R' so that if the person thinks they have messed up they can start again fast without having to come out and refresh the page.
Well done on completing a game, you should all be really pleased. As stated, I can definitely see what this game could be, I hope you continue to work on it and tweak it as I think that could be a really fun and interesting puzzle