/* =========================================================================
   SILVER ART DECO - the site palette since November 2026

   Layered over site.css: active with <html data-palette="silver">, which
   layouts/base.njk sets on every page. The Art side keeps its celadon.
   The print sheets (layouts/print.njk), the sims, the tag chips and the
   figures keep their own colours. To return to the warm palette, remove
   the attribute in base.njk.

   Derivation: the warm greys at the same OKLab lightness, the hue turned
   to 245 (cool) and the chroma x0.45, so every contrast ratio, by day and
   by night, is unchanged. The accent is steel, the same hue at about 3x
   the greys' chroma: gunmetal for links by day, polished silver by night.
   "Laboratory" is silver beside the ink of the name, and the rule
   diamonds are faceted metal, lit from the upper left.
   ========================================================================= */

:root[data-palette="silver"]:not([data-mode="gallery"]) {
  --grey-50:  #F2F4F6;
  --grey-100: #E8EAEC;
  --grey-200: #D8DADD;
  --grey-300: #C3C7CA;
  --grey-400: #ADB1B4;
  --grey-500: #969A9D;
  --grey-600: #7E8285;
  --grey-700: #626669;
  --grey-800: #474B4E;   /* cards by night */
  --grey-900: #2E3235;   /* the night ground */
  --ink:   #25282B;
  --paper: #F8F8F9;

  /* Steel, the accent */
  --steel-100: #EAEFF4;
  --steel-300: #C3CCD3;
  --steel-400: #ABB6BF;
  --steel-600: #7A858F;
  --steel-700: #5B6670;
  --steel-800: #3F4952;

  --link:     var(--steel-800);   /* 8.65:1 on paper */
  --accent:   var(--steel-800);
  --focus:    var(--steel-800);
  --divider:  var(--steel-600);
  --suffix:   var(--steel-600);   /* 3.55:1 on paper, display size only */
  --accent-on-light: var(--steel-800);
  --accent-on-dark:  var(--steel-300);

  /* The four facets of the rule diamonds, brightest first */
  --facet-1: var(--steel-300);
  --facet-2: var(--steel-400);
  --facet-3: var(--steel-700);
  --facet-4: var(--steel-800);

  --frost-light: 248 248 249;
  --frost-dark:  27 29 31;
  --frost-ground-dark: 46 50 53;
  --deck-ink-light: rgb(240 243 247);
  --deck-ink-dark:  rgb(104 118 140);
}
@media (prefers-color-scheme: dark) {
  :root[data-palette="silver"]:not([data-mode="gallery"]) {
    --link:     var(--steel-100);   /* 11.2:1 on the ground */
    --accent:   var(--steel-100);
    --focus:    var(--steel-100);
    --divider:  var(--steel-300);
    --suffix:   var(--steel-400);   /* 6.3:1 */
    --facet-1: var(--steel-100);
    --facet-2: var(--steel-300);
    --facet-3: var(--steel-600);
    --facet-4: var(--steel-700);
  }
}

/* "Laboratory" in silver. Over the homepage imagery it follows the
   header's light or dark chrome, as the accent does. */
:root[data-palette="silver"]:not([data-mode="gallery"]) .wordmark__suffix--lab { color: var(--suffix); }
:root[data-palette="silver"]:not([data-mode="gallery"]) body.is-deck .site-header { --suffix: var(--steel-300); }
:root[data-palette="silver"]:not([data-mode="gallery"]) body.is-deck .site-header--on-light { --suffix: var(--steel-600); }

/* The rule diamonds as cut metal: four facets (the diamond is a square
   turned 45 degrees, so the conic gradient's quarters are its facets). */
:root[data-palette="silver"]:not([data-mode="gallery"]) .rule::after,
:root[data-palette="silver"]:not([data-mode="gallery"]) .page::after {
  background: conic-gradient(from 45deg, var(--facet-4) 0 25%, var(--facet-3) 0 50%, var(--facet-1) 0 75%, var(--facet-2) 0);
}