Comment form problem for Mobility on mobile phones

[carisma_sensei]

Hi! I created a Mobility layout the other day, which can be seen here, and the person who is using it pointed out that this problem was happening on mobile phones.

She said that when checking "use layout's stylesheet", it disappeared. So I don't know what gives! Since I'm new to Mobility, maybe there's something wrong with comment pages.

Anyone could help me out a bit? Thanks!