/* Spacing, radii, borders & shadows — Tide & Copper
   Calm, generous layouts on warm paper. Panels are square-cornered with hairline borders;
   cards get a soft ground shadow. Nothing bounces. */

:root {
  /* ---- Spacing scale (4px base) ---- */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 22px;
  --space-6: 32px;
  --space-7: 46px;
  --space-8: 60px;
  --space-9: 84px;

  /* ---- Radii ---- */
  --radius-none: 0px;
  --radius-sm:   6px;   /* buttons */
  --radius-md:   7px;   /* cards, swatches */
  --radius-lg:   9px;   /* stages, panels */
  --radius-pill: 40px;  /* pills & badges */

  /* ---- Borders ---- */
  --border-hair: 1px solid var(--paper-line);
  --border-strong: 1.5px solid var(--deep-tide);
  --rule-copper: 3px solid var(--copper);   /* the signature left rule */

  /* ---- Shadows ----
     Two-layer: a warm 2px "shelf" plus a soft deep-tide ground shadow. */
  --shadow-shelf:  0 2px 0 var(--paper-line);
  --shadow-card:   0 2px 0 var(--paper-line), 0 10px 24px -18px rgba(22,38,43,.5);
  --shadow-raised: 0 12px 26px -18px rgba(20,65,76,.6);
  --shadow-cover:  0 18px 40px -22px rgba(20,65,76,.7);
  --shadow-btn:    0 3px 0 #8C4123;   /* copper button shelf */
  --shadow-btn-dark: 0 3px 0 #0C2A32; /* deep tide button shelf */

  /* ---- Motion ----
     Quiet fades and small lifts. No bounce, no spring. */
  --ease-standard: cubic-bezier(.2, .6, .3, 1); /* @kind other */
  --dur-fast: .15s; /* @kind other */
  --dur-base: .2s;  /* @kind other */
  --lift-hover: translateY(-3px); /* @kind other */
}