Sunday night, designer John Varvatos held his 11th Annual Stuart House Benefit alongside honorary co-chairs Amy Adams and fiancée Darren Le Gallo. But this time around, the actress swapped a flowing gown for something more casual on the red carpet — denim.

“I didn’t actually put that much thought into it,” Adams exclusively tells InStyle.com. “It wasn’t until I was on the red carpet that I realized I’ve never worn tight pants on the red carpet.” The Oscar winner paired her denim with black caged platform heels, navy blazer, and peach bow-neck blouse.

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The event, which included a charity concert and auction, called for relaxed attire—a dress code that seemed foreign to Adams, given her glamorous red carpet track record this awards season. All the proceeds fund a treatment program for sexually abused children at the Santa Monica-UCLA Medical Center. “About five years ago, someone reached out to me to host a brunch for the rape treatment center and the Stuart House, so I went down and took a tour,” remembers Adams. “What they do is so impactful and so amazing.”

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With reporting by Scott Huver