How to reduce the width of a text field?

See Max & min length options and character count

Thank you Takayuki Miyoshi, but that is not, what I was looking for. I want to reduce the width of a text field to two characters. The explanation from the document you linked, I had already taken into account, as you may see from the code in my question.

See Form-tag syntax

Sorry, that link doesn’t help at all. Wich part of the explainations on that site should do the trick?

Probably

Note that order of those parts is important. Options can’t come before name, and values can’t come before options.

Sorry, that doesn’t help me. Can you be more specific?