The web prompter

Present from any browser, with keyboard or touch.

Controls

`Space`	Play / pause (skips a pause countdown)
`← / →`	Slower / faster
`↑ / ↓`	Scroll back / forward
`+ / −`	Bigger / smaller text
`M`	Mirror (for beam-splitter glass)
`F`	Fullscreen
`R`	Back to the start