SmolDataEnvs: fill empty file lists in 424 rows

Card: drop em dashes

Card: FineEnvs citation

Card: full banner on top

Card GIF: hill climb only, no banner band

README: the curves loop now carries the banner

README: light-theme curves, split train | eval, shuffled vs curriculum

README: quote the tagline, add the training-curve loop

README: fix the data-pull and grader snippets

SmolDataEnvs: rename, new README, banner

Upload README.md with huggingface_hub

Upload grader.py with huggingface_hub

Upload dataset

initial commit