/* ============================================================
   S4SF — Spacing, radius, shadow, motion, layout
   ============================================================ */
:root {
  /* Spacing scale (4px base) */
  --space-0: 0;
  --space-1: 0.25rem;   /* 4 */
  --space-2: 0.5rem;    /* 8 */
  --space-3: 0.75rem;   /* 12 */
  --space-4: 1rem;      /* 16 */
  --space-5: 1.5rem;    /* 24 */
  --space-6: 2rem;      /* 32 */
  --space-7: 3rem;      /* 48 */
  --space-8: 4rem;      /* 64 */
  --space-9: 6rem;      /* 96 */
  --space-10: 8rem;     /* 128 */

  /* Corner radii — the brand mark is fully circular; UI uses
     soft, generous rounding to echo that geometry. */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 28px;
  --radius-pill: 999px;
  --radius-circle: 50%;

  /* Shadows — soft, cool, low-contrast (blue-tinted) */
  --shadow-xs: 0 1px 2px rgba(17, 19, 32, 0.06);
  --shadow-sm: 0 2px 8px rgba(20, 25, 143, 0.08);
  --shadow-md: 0 8px 24px rgba(20, 25, 143, 0.10);
  --shadow-lg: 0 18px 48px rgba(20, 25, 143, 0.14);
  --shadow-brand: 0 12px 32px rgba(28, 36, 196, 0.28);

  /* Focus ring */
  --ring: 0 0 0 3px rgba(62, 221, 206, 0.55);

  /* Motion */
  --ease-standard: cubic-bezier(0.4, 0, 0.2, 1); /* @kind other */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1); /* @kind other */
  --dur-fast: 120ms; /* @kind other */
  --dur: 200ms; /* @kind other */
  --dur-slow: 340ms; /* @kind other */

  /* Layout */
  --container: 1200px; /* @kind other */
  --container-narrow: 820px; /* @kind other */
}