:root{
  --dur-instant:90ms; --dur-fast:150ms; --dur-base:220ms; --dur-slow:380ms; --dur-reveal:620ms;
  --ease-out:cubic-bezier(0.22,0.61,0.36,1); --ease-in-out:cubic-bezier(0.4,0,0.2,1); --ease-settle:cubic-bezier(0.16,0.84,0.44,1);
  --transition-control:background-color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out), box-shadow var(--dur-fast) var(--ease-out);
  --transition-card:transform var(--dur-base) var(--ease-settle), box-shadow var(--dur-base) var(--ease-out);
}