Jessica Simpson’s latest outfit proves that seasonal dressing is a mere suggestion — not a rule.

The “I Wanna Love You Forever” singer was seen attending the We Matter x Limitless Mental Health Dinner on Saturday, May 31, in Los Angeles, in a outfit that channeled gothic glam, despite summer being around the corner.

For the event, the singer wore a black satin mini slip dress with lingerie-inspired lace trim around the bust, which featured a subtle dip that showed off a hint of Simpson’s cleavage.

The 44-year-old paired the slip dress with black back seam stockings, pointed black patent leather boots, and a black feathered cropped jacket. Simpson further accessorized the edgy ensemble with rows of silver and gold bracelets, matching necklaces and a large turquoise stone ring worn on her right hand.

Simpson has been experimenting with her style in recent weeks. The singer delivered her first television performance in 15 years on American Idol‘s finale on May 18, and looked dazzling — literally — for the occasion.

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The fashion designer wore a plunging silver metallic maxi dress with a thigh high slit at the hip. Simpson paired the look with unexpected rustic elements and accessorized with an oxidized silver belt with turquoise stones that sat low on her hips. The belt matched the pendant detail at the dress’ plunging neckline, as well as the other accessories she layered, which included necklaces, rings and earrings.

During her time on the telecast, Simpson sang “Blame Me” from her Nashville Canyon, Pt. 1 album and was later joined by former contestant, Josh King; they performed her 2005 cover of “These Boots Are Made for Walkin’” from the Dukes of Hazzard soundtrack.

Simpson later told Extra how nervous she was to appear on television for the American Idol season finale.

“I just kept telling myself, ‘Do not cry. Do not cry. I know this is a big moment … do not cry.’ And then I see my dad, like, up in the corner, and I’m like, ‘Ah, I’m going to cry. I’m going to cry. Do not cry. Just sing your songs. Just sing your songs,’ ” she recalled, adding that she even used hairspray to keep her feet in place and stop her from sweating.

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The turquoise elements continued in Simpson’s surprise stage performance at the Luck Reunion on March 13, in Spicewood, Texas.

For her set, she went bold in a cheetah print bodycon dress that she wore with a crochet shrug. Similar oxidized silver belts and chains were worn around her waist and neck, and she accessorized with multiple turquoise rings.