Casual-wear can be cut with carelessness reminiscent of the path of the meatball rolling down its front. For laid-back gear constructed as deliberately as a space station, try Turk + Taylor
Offering a full line of classically-inspired, chilled-out duds, T+T's a local brand named after the seedy Tenderloin intersection -- a wiser moniker than that chosen by "6th between Mission and Market", makers of feces-scented overalls.
Relying solely on proprietary patterns, their limited-edition collection ranges from a lumberjack dress shirt made from sturdy cotton instead of flannel (all the scruff, none of the fuzz) to a "sustainable" silk hoodie, i.e., before the cocoon's boiled, the worm's allowed to escape, then retire to the bottom of your mezcal.
Button-downs feature mother-of-pearl hardware, and most pieces come w/ signature neon-green lining, and seam-work so streamlined you could wear your clothes inside out, were you to join a child rap group
While T+T's t-shirts are in stores, much of their stuff's currently only available by appointment at their studio, which you should casually roll down to -- because sometimes, the meatball is you.