/* tokens.css — design tokens for Show My Math.
 * Kid-friendly but parent-readable: warm cream background, soft tinted cards,
 * place-value blocks colored for ~3:1 contrast and shape redundancy.
 */
:root {
  /* ----- Color: surfaces ----- */
  --color-bg:           #FAF7F2;       /* warm near-white */
  --color-surface:      #FFFFFF;       /* card */
  --color-surface-tint: #FFF6E8;       /* lightly warm card alt (for inputs / step desc) */
  --color-border:       #E7E2D8;       /* subtle */
  --color-border-strong:#C9C2B3;

  /* ----- Color: text ----- */
  --color-text:         #2A2723;       /* warm near-black */
  --color-text-muted:   #6B6657;
  --color-text-subtle:  #9A9485;

  /* ----- Color: brand / focus ----- */
  --color-accent:       #2563EB;       /* calm blue, for focus / current step */
  --color-accent-soft:  #DBE8FF;
  --color-accent-ink:   #1E3A8A;

  /* ----- Color: place-value families ----- */
  --color-hundreds:     #6366F1;       /* indigo */
  --color-hundreds-soft:#E0E1FF;
  --color-tens:         #0D9488;       /* teal */
  --color-tens-soft:    #CFF1EB;
  --color-ones:         #F59E0B;       /* amber */
  --color-ones-soft:    #FFEAC1;

  /* ----- Color: state ----- */
  --color-strike:       #E11D48;       /* coral-red cross-out */
  --color-strike-soft:  #FFD9DF;
  --color-success:      #059669;       /* answer reveal */
  --color-success-soft: #C8F1DF;
  --color-warning:      #C2410C;
  --color-warning-soft: #FFE6D2;

  /* ----- Spacing scale ----- */
  --space-2x:  4px;
  --space-1x:  8px;
  --space-2:  12px;
  --space-3:  16px;
  --space-4:  24px;
  --space-5:  32px;
  --space-6:  48px;
  --space-7:  72px;

  /* ----- Radius ----- */
  --radius-sm:  6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-pill: 999px;

  /* ----- Shadows ----- */
  --shadow-1: 0 1px 2px rgba(20, 16, 8, 0.05), 0 1px 1px rgba(20, 16, 8, 0.04);
  --shadow-2: 0 4px 12px rgba(20, 16, 8, 0.06), 0 2px 4px rgba(20, 16, 8, 0.04);
  --shadow-3: 0 12px 32px rgba(20, 16, 8, 0.10), 0 4px 8px rgba(20, 16, 8, 0.05);
  --shadow-focus: 0 0 0 3px var(--color-accent-soft);

  /* ----- Typography ----- */
  --font-sans: -apple-system, "Segoe UI Variable", "Segoe UI", Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  --font-serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --font-tabular: "SF Mono", "Cascadia Mono", "Consolas", "Liberation Mono", monospace;

  --fs-xs:   14px;
  --fs-sm:   16px;
  --fs-base: 18px;
  --fs-md:   20px;
  --fs-lg:   24px;
  --fs-xl:   30px;
  --fs-2xl:  38px;
  --fs-3xl:  48px;

  --lh-tight: 1.2;
  --lh-snug:  1.35;
  --lh-base:  1.55;

  --fw-regular: 400;
  --fw-medium:  500;
  --fw-semibold: 600;
  --fw-bold:    700;

  /* ----- Motion ----- */
  --ease-standard: cubic-bezier(.4, 0, .2, 1);
  --ease-emphasis: cubic-bezier(.34, 1.56, .64, 1);  /* slight overshoot for reveals */
  --ease-out:      cubic-bezier(0, 0, .2, 1);
  --ease-in:       cubic-bezier(.4, 0, 1, 1);

  --dur-fast:    150ms;
  --dur-base:    250ms;
  --dur-slow:    400ms;
  --dur-step:    700ms;   /* default per-step animation duration */

  /* ----- Layout ----- */
  --layout-max:    1100px;
  --layout-narrow: 760px;
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --dur-fast: 1ms;
    --dur-base: 1ms;
    --dur-slow: 1ms;
    --dur-step: 1ms;
  }
}