I love this game! Such a cool idea, and very well executed.

My biggest critique so far is that it's extremely hard for me to tell the difference between #311 and #000 for the `.disabled` lines (I'm mildly red-green colorblind). Changing it to #711 fixed it for me, but I can imagine it would be impossible to even see #F11 for certain colorblind individuals. Perhaps some other kind of indication that a line is editable, or a more drastic #FFF/#000 distinction?