Jainism does not have a universal ban or rule that says girls cannot wear short dresses. The tradition emphasizes modesty, cleanliness, non-violence, and respectful conduct. What matters most is the intention, avoiding harm to living beings in clothing production, and fitting the local community’s Maryādā (custom/dress norms) where you are.

Key points:

• Digambar and Śvetāmbar traditions differ in monastic rules (Digambar monks practice nudity; Śvetāmār monks and nuns wear simple white robes). For laypeople, dress codes are mainly about modesty and simplicity, not a fixed universal standard.
• Local temples or sangh communities often set their own guidelines about dress to maintain decorum; this can include more modest attire for women in some places, but it isn’t a canonical injunction against short dresses everywhere.

You can read more here and here .

If you want, tell me your specific tradition or temple, and I can describe the common local norms.