Gucci - Detachable purple crystals decorate the uppers of Gucci's khaki-green Flashtrek low-top trainers, which were first spotted on the house's AW18 runway. Taking inspiration from hiking books, they're crafted from a combination of leather, mesh and suede, and set on a chunky rubber lug sole. Let them add a striking accent to a black sweater and pleated midi skirt.