/*
  IDENTITY LAYER · design tokens
  Reusable AISA look: color, type, tracking, borders, radii.
  Provisional campaign reference (Sept 9 newsletter), not an official brand guide.

  Change a value here and every banner, the presentation view and the
  discussion graphic pick it up. Per-format sizes live in formats/*.css.
*/
:root {
  /* Color. Contrast (measured): ink/field 15.87:1, accent/field 4.97:1.
     Never set ink text on accent or accent text on ink (3.19:1). */
  --bk-color-field: #FFF8F3;   /* warm cream: banner background */
  --bk-color-ink: #1D1E20;     /* charcoal: text, strips, borders, one graphic path */
  --bk-color-accent: #2A7A57;  /* deep green: program label, co-brand tag, graphic */

  /* Type families. Libre Baskerville for headlines, dates and partner line;
     Barlow for labels and body. Fallbacks are listed in DRAFT_specification.md. */
  --bk-font-serif: 'Libre Baskerville', Georgia, 'Times New Roman', serif;
  --bk-font-sans: Barlow, 'Helvetica Neue', Helvetica, Arial, sans-serif;

  /* Tracking (letter-spacing) for each text role. */
  --bk-track-headline: -0.01em;
  --bk-track-strip: 0.08em;
  --bk-track-strip-note: 0.06em;
  --bk-track-program: 0.14em;
  --bk-track-tag: 0.1em;
  --bk-track-label: 0.12em;
  --bk-track-logo: 0.08em;
  --bk-track-cta: 0.02em;

  /* Line heights shared by every format. */
  --bk-leading-tight: 1;
  --bk-leading-description: 1.35;
  --bk-leading-partner: 1.2;
  --bk-leading-small: 1.3;

  /* Unconfirmed content is always boxed with a dashed ink border. */
  --bk-pending-border: 2px dashed var(--bk-color-ink);
  --bk-pending-border-strong: 3px dashed var(--bk-color-ink);
  --bk-outline: 2px solid var(--bk-color-ink);
  --bk-outline-strong: 3px solid var(--bk-color-ink);
  --bk-outline-accent: 2px solid var(--bk-color-accent);

  --bk-radius-box: 4px;
  --bk-radius-box-lg: 6px;
  --bk-radius-pill: 999px;
}