Business casual. I've seen folks in shorts too. Very low key.
The upper-end of casual, really. I go to shows all the time in nice jeans and a polo.
Nice, but not formal by any means. I've worn jeans with a nice blouse. And I've worn a dress. Both were totally fine.
I went to an evening show and most were well dressed.
I usually wear a dress but I go to the evening shows which are a little more formal but not much.
I've seen it vary due to the heat but I wouldn't worry to much about it. Business casual for sure.
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