First turn your keyboard 90 degrees counter clockwise! Then select your layout (most likely QWERTY I think).

Now imagine your hand is a little guy or spider that wants to climb from the 1st, bottom row ("1,Q,A,Z" on a QWERTY layout) to the 9th row ("9,O,L,Period"). To climb you'll have to hold on to the keys you've already reached and try out the keys higher up to get a grip on them.

Check out this image to see the area.

I've added support for QWERTY (EU and US), AZERTY and Dvorak layouts. Let me know if I'm missing a common layout, I'll see if I can add it.

Screen output

Black screen means you're at the bottom and not climbing or holding on.
Blinking means you've just pressed a valid key and are about to grab it.
Solid color means you're holding on to all the keys you're currently pressing and ready to move on.
When you reach and grab a key on the final row the screen will flash rapidly for a few seconds and go blank. You've made it! Try again!

Rules

Only play with one hand! (the game doesn't know, obviously, but no cheating)
You can only climb to a row if you're already holding two keys on the row before it. (doesn't apply to the first row of course)
If you're holding less than two keys you'll fall down.
Your grabbed keys can't span more than three rows, you'll have to let go of the lower keys as you move up.
A few random keys are blocked to make it harder, and because of the way keyboards work, some combinations of simultaneous key presses will block other keys, this is all part of the challenge! Try moving around on your current row if you're stuck.
(Pressing Tab will show/hide some debug info about which buttons are pushed, but that's cheating)

I hope it makes sense, drop a line in the comments if you have questions or suggestions.

Jam rules disclaimer thing: Yes, there are buttons for choosing the keyboard layout, but I have no idea how to detect which layout you have (or if it's even possible in the browser). The game itself is purely 1-bit and the alternative might be something silly like separate downloads for each layout ;)