Now that's a healthy little seedling well done . . .
My only moan . . . . . . is that tin foil used to not reflect the correct spectrum? A matt white surface has more reflectivity. It may look bright in there, but is that brightness containing the spectrum / PAR you need??? I doubt it. Though it is growing beautifully. Perhaps 1/4 turn it every few hours so defo no hot spots start getting to work.
Well done though, nice littlun . . . .. what's the strain please??