:root{
  /* 4px base grid */
  --space-0:0px;
  --space-1:4px;
  --space-2:8px;
  --space-3:12px;
  --space-4:16px;
  --space-5:20px;
  --space-6:24px;
  --space-8:32px;
  --space-10:40px;
  --space-12:48px;
  --space-16:64px;
  --space-20:80px;
  --space-24:96px;
  --space-32:128px;

  /* Semantic spacing */
  --gutter-inline:24px;          /* mobile page gutter */
  --gutter-inline-lg:48px;       /* desktop page gutter */
  --section-y:96px;              /* vertical rhythm between marketing sections */
  --section-y-tight:64px;
  --stack-tight:8px;
  --stack:16px;
  --stack-loose:24px;
  --control-pad-x:20px;
  --control-pad-y:12px;
  --card-pad:24px;

  --measure-prose:68ch;
  --container-max:1240px;
  --container-narrow:760px;

  --control-h-sm:32px;
  --control-h-md:44px;
  --control-h-lg:54px;
}