:root{
/* Corners: the brand is print-flat. Cards are square-ish; only pills and
   the ribbon depart from it. Never use large soft radii. */
--radius-0:0;
--radius-1:2px;
--radius-2:4px;      /* default card / input */
--radius-3:8px;      /* badge, chip */
--radius-pill:999px;
--radius-card:var(--radius-2);
--radius-button:var(--radius-2);
--radius-input:var(--radius-2);
--radius-badge:var(--radius-pill);

/* Widths */
--border-hair:1px;
--border-1:1.5px;
--border-2:3px;      /* card outline on the catalog */
--border-3:5px;      /* the blue rule under the header */
--border-rule-gap:3px; /* gap between the two lines of a double rule */

/* Semantic borders */
--border-card:var(--border-1) solid var(--line-card);
--border-card-strong:var(--border-2) solid var(--line-strong);
--border-accent:var(--border-2) solid var(--line-rule);
--border-input:var(--border-1) solid var(--line-card);
--border-input-focus:var(--border-1) solid var(--blue-600);

/* The signature blue double rule, as a reusable background */
--rule-double:repeating-linear-gradient(to bottom,var(--pen-blue) 0 3px,transparent 3px 6px);
}