The few hosts which support site management from primitive web browsers like the DSi's are expectedly limited, especially when it comes to stylesheets.
If you want to only host CSS files, you are better off using a cloud hosting service like Dropbox. If you're making a website also, use proper website hosting.
'The Real Problem with Real Life is There's No BGM'
By Limxzero (5329)
By GuitarGodAnth (273)
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