Halfway between that stiff, sweat-trapping blazer and those comfy but overly revealing tank tops lies an ideal way to dress for hot-weather desk duty. A snappy jacket and some retro styling can resolve the dilemma stylishly (besides, arctic air-conditioning demands some kind of cover-up). Start with a trimly tailored YSL safari style, a feminized seersucker blazer, or an oversize boyfriend-jacket (a fringe benefit of the eighties resurgence). Add some brightly colored accessories and a pair of glossy pumps, assemble it all over something skinny, like jodhpurs or tiny shorts, and admire your ability to achieve perfect compromise.