Rain sounds for studying.
A study night has a quiet enemy, and it isn't noise. It's sudden noise — the door, a phone down the hall, a voice that rises without asking. Steady rain is the opposite of sudden: it arrives and never changes shape, so your ears run out of things to report. An ear with nothing new is where concentration starts.
The rain also covers what would otherwise interrupt. The street, the pipes, the conversation through the wall — under it they're one continuous hush with no edges, and an interruption without edges doesn't interrupt. Your attention isn't pulled, because there's no single moment to pull it.
Dark rain is the working kind. It's the low, even rain you hear from under a roof rather than out in it — no bright patter on the window, no hiss, no chorus of small drops to pull the ear outside. Just the steady weight of it, level the whole session, which is exactly what a long chapter asks for.
Set it up once and let it run. Soft light, the phone face-down where you can't see it, the sound a shade quieter than you'd expect. The session runs fifteen minutes and ends on its own, and one tap brings it back if the work isn't finished.
Dark rain is waiting above, one tap away. Low and steady, from the first line to the last.