/* ===========================================================================
   AIlin — Spacing, radii, shadows, borders, motion
   ---------------------------------------------------------------------------
   Editorial restraint: a 4px base grid, modest radii, soft warm-tinted
   shadows. Hairline borders do most of the structural work; shadows are a
   quiet accent, never a crutch.
   =========================================================================== */

:root {
  /* ---- Spacing (4px base grid) ---- */
  --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:  2.5rem;   /* 40 */
  --space-8:  3rem;     /* 48 */
  --space-9:  4rem;     /* 64 */
  --space-10: 5rem;     /* 80 */
  --space-12: 7rem;     /* 112 */

  /* ---- Radii (restrained, editorial) ---- */
  --radius-xs:  3px;
  --radius-sm:  6px;
  --radius-md:  9px;   /* default control / card inner */
  --radius-lg:  13px;  /* cards, panels */
  --radius-xl:  18px;  /* large surfaces */
  --radius-pill:999px;
  --radius-circle:50%;

  /* ---- Borders ---- */
  --border-hairline: 1px solid var(--border-default);
  --border-subtle-1: 1px solid var(--border-subtle);
  --border-strong-1: 1px solid var(--border-strong);
  --border-width: 1px;

  /* ---- Shadows (warm-tinted, low, quiet) ---- */
  --shadow-xs:  0 1px 2px rgba(40, 33, 20, 0.05);
  --shadow-sm:  0 1px 2px rgba(40, 33, 20, 0.05),
                0 2px 6px rgba(40, 33, 20, 0.05);
  --shadow-md:  0 2px 4px rgba(40, 33, 20, 0.04),
                0 6px 16px rgba(40, 33, 20, 0.08);
  --shadow-lg:  0 4px 10px rgba(40, 33, 20, 0.06),
                0 18px 40px rgba(40, 33, 20, 0.12);
  --shadow-xl:  0 12px 28px rgba(40, 33, 20, 0.10),
                0 40px 80px rgba(40, 33, 20, 0.16);
  --shadow-inset: inset 0 1px 2px rgba(40, 33, 20, 0.06);

  /* ---- Motion ---- */
  --ease-out:   cubic-bezier(0.22, 0.61, 0.36, 1); /* @kind other */
  --ease-inout: cubic-bezier(0.65, 0.05, 0.36, 1); /* @kind other */
  --ease-spring:cubic-bezier(0.34, 1.56, 0.64, 1); /* @kind other */
  --dur-fast:   120ms; /* @kind other */
  --dur-base:   200ms; /* @kind other */
  --dur-slow:   340ms; /* @kind other */

  /* ---- Layout ---- */
  --sidebar-w:    248px;
  --container-w:  1200px;
  --reading-w:    680px; /* transcript column */
}