Not too long ago, it was all about the mom jeans and shrunken moto jacket. Before that, it was black skinnies and the threadbare white tee (preceeded by leggings and an oversized flannel). The two-piece cool-girl uniform du jour is an instantly recognizable look, no matter if you hail from Brooklyn, L.A., Berlin, or Shanghai — if you're in the know, you will get the memo. If you weren't, you will be as soon as you finish peeking these pics.

A mock-neck top and high-waisted skirt marry two very strong trends but strip them of nostalgia: '70s silhouettes and '90s minimalism. A ribbed layering shirt and fun skirt has hints of Marcia Brady, but this time without the kitschiness of flower-power prints and colors. Go longer with the skirt and more minimal with the top, and you get an outfit that'd fit in the Paris Fashion Week scene. Keep both pieces on the more conservative side, and you've got a simple look for work that you'd still rock for drinks afterward. Click through to see more versions of this simple formula and start mix-and-matching your own fall uniform.