Leather look leggings are a great staple for your wardrobe whether you're under or over 40. They create a more edgy look and a dressier feel than a plain knit legging.
You can find them with a plain front, or with some pattern like these, which I thinks makes for a more interesting garment.
I think they work well with a chunky heel ankle bootie that fits fairly close to your ankle for a more uninterrupted line.
A long loose cardigan or jacket makes the outfit flow. Remember the principle of volume - only one voluminous garment at a time -so the longline cardigant or a loose tunic top work well with your slim fitting leather look leggings.
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