Haley Bieber doesn't shy away from trying unexpected coordinates, whether it's a chainmail skirt for the beach or mesh flat shoes for the office. As the founder of Lorde, she incorporates a little experimentation and a Haley Bieber twist into every look, while still basing it on universal conventions. Her latest look is no exception: over the weekend, Bieber wore an off-duty outfit that perfectly encapsulates her personal style: sporty, minimal, and with a twist, very Los Angeles.

As L.A. finally began to feel the winter chill, the 27-year-old turned her favorite black micro-mini skirt into a more weather-appropriate ensemble. For starters, Bieber layered a leather blazer from respected celebrity fashion brand Khaite. Her blazer has an oversized fit (a silhouette Bieber often wears) and a slightly cinched waist. Underneath the luxe leather jacket, she wore a cropped rugby shirt from Loewe, expressing Bieber's preference for sporty pieces with a relaxed, nonchalant vibe.

Normally, one would expect Bieber to pair an oversized blazer with equally oversized denim bottoms, but not this time. Instead, she defied our style expectations by opting for straight-leg jeans. (But let's be clear about one thing: these are not necessarily skinny jeans, but a form-fitting, straight-leg style.)

Then, as a tribute to Princess Diana's casual street style, she added a few accessories: a navy baseball cap and oval sunglasses. Finally, she carried a tote bag from THE ROW and wore Bottega Veneta's ubiquitous drop earrings.

You've probably seen A-listers in similar outfits before, which shows how solid her view of style is. There is nothing more effective than an obvious way of dressing to show that you "know yourself and your fashion. And in Bieber's case, it appears to be vintage-inspired items, lots of denim, quiet luxury brands, and one or two statement pieces.

If you're inspired by Bieber's West Coast winter outfits, lucky for you, hers are surprisingly easy to copy. Start with your favorite jeans and follow Bieber's example by adding vintage-inspired pieces like a rugby shirt and baseball cap. Highlights of her look, including rugby shirts, denim, loafers, and a blazer, can be purchased below.