The filling of the patterns feels very, very satisfying. Between that and the "tome" concept the mind immediately drops lore possibilities, like "am I making a grimoire of some sort? Demon binding circles? Different levels of meditation?". The mechanics between different layers are varied enough that each feels different although I'll agree with some of the other comments that the final red stretch is a bit much, especially since the mechanic for that particular stage involves both holding down the button and waiting for an amount of time, not really letting the player either focus on it completely or just drift away and let it charge. You'd think the blue part of this stage would have a similar problem but it just feels shorter both in how many shapes you have to get and in the actual wait to be able to click.
Dunno if I feel the theme was that well addressed, the no text part is definitely there but the different colours don't feel like they are "contained" within one another but rather just different concurrent levels. Still, one of the better entries I've seen so far.