Ok, so I'm new to SF and thought this would be the best place to ask this question. I'm going out to dinner with my girlfirend and was curious as to what kind of shirt I should wear. I'm 20 years old so nothing to "grown up" and don't want to spend TOO much money, under $100 if possible. I would like to just go to the mall and pick one up if possible, just need to know what brands/stores to visit. Any help is appreciated.