/* ===========================================================================
   ForbocAI — Hearthlight
   ---------------------------------------------------------------------------
   The page descends from day into night. Parchment carries the hero and the
   capability ledger; from the Soul Garden onward everything sits on deep moss,
   so the lantern light in the brand finally has something to light.

   Palette is pinned by design_ref/palette.md. Type is Vollkorn for headings,
   Alegreya Sans for everything read at length, Eagle Lake for the wordmark and
   nothing else.
   ======================================================================== */

:root {
    /* Day — parchment side */
    --day-bg: #f4ead7;
    --day-bg-deep: #ede0c7;
    --day-surface: #fbf6ea;
    /* A hairline has to be a hairline on the WHOLE descent, not only at the
       top of it. #ddcdae measured 1.012:1 against #technology's --dusk-0
       ground — the ledger's row dividers were unpainted along their whole
       length, and what looked like a taper was a decorative colony passing
       underneath them. These clear 1.3:1 against the darkest day ground and
       still read as a hairline against the lightest. */
    --day-rule: #c7ae87;
    --day-rule-soft: #d8c6a4;
    --day-ink: #263127;
    --day-ink-soft: #5c4a3b;
    /* Both "faint" inks carry real sentences, not decoration, and both measured
       just under AA at 15-19px once the grounds were lit: --day-ink-faint at
       4.23 on .ledger-fact and 4.40 on a disclosure label, --night-ink-soft at
       3.96 on .soul-market and 4.00 on #room's prose. A tone that has to be
       read is not allowed to be the faintest thing that will still pass — it
       has to pass. Each moves one step toward its own ink and no further, so
       the tier below the body copy survives. */
    --day-ink-faint: #4c4132;

    /* Night — moss side */
    /* Deep moss, not grey with a green tint.

       The night ground was #263127 — an RGB range of 11, which is a grey.
       Rendered, every night chapter measured chroma 13-17 out of 255 across
       53-58% of the scroll, and the brief's "cosy" half was failing on the
       dark side of the page because a lantern in a grey room is a lit
       specimen, not an inn.

       Each token keeps its luminance to within a point of the old #263127
       (46.6) so nothing that clears AA today stops clearing it; only the
       saturation moves, roughly doubling.

       And the hue sits at olive-moss (~100°), not blue-green (~138°). The first
       saturated pass went blue-green and read as a cold field: the lamps mix
       into the ground, and a lantern over blue-green comes out grey-green,
       which dropped the warm share of the brightest pixels from 80% to 42% in
       #turn. Over olive the same lantern comes out amber. Overgrowth is green;
       the light in it is warm; the ground has to let the light stay warm. */
    --night-bg: #253321;
    /* The night has a floor, and the way down to it.
       Measured over the whole page in its own left gutter, the day drifted 29
       luminance levels across three chapters, fell 137 in one 400px cliff, and
       then the six night chapters sat inside 13 levels of each other with no
       direction at all — #roadmap and #souls BRIGHTER than #turn, because what
       varied was the colony lighting and not the ground. A page whose one idea
       is a continuous descent spent its whole back half not descending.
       --night-bg stays the night you arrive in; these are where it goes. */
    --night-mid: #1c2715;
    --night-floor: #121a0c;
    --night-surface: #2c3d27;
    --night-surface-high: #35492e;
    --night-rule: #3f5248;
    --night-ink: #f1e8d6;
    --night-ink-soft: #d4dcc9;
    --night-ink-faint: #93a18b;

    /* Lantern and accents */
    --lantern: #fff3c2;
    --honey: #e0c38a;
    --copper: #a46a3f;
    /* #a46a3f clears 3:1 as a rule or border but only reaches 3.7:1 as text
       on parchment, so anything set in copper uses this darker ink. */
    --copper-ink: #6b4429;
    --ember: #d9896d;
    --creek: #7aa7b3;
    --sage: #9dbb8b;

    /* The grown light's own hues. --creek and --sage are surface colours —
       muted, low-saturation, correct for a wall in the dark and useless as a
       light source, which is why a two-source model built on them still read as
       one source. Bioluminescence is saturated; that is the whole visual fact
       of it. These two are for EMISSION only and never for a surface or ink. */
    --biolume-core: #5fe3cd;   /* fungal cyan — the colony on the shaded side */
    --spore: #a98cf5;          /* spore violet — rarer, deepest night only */
    --mint: #cfe9dc;
    --lavender: #bda6cf;

    /* The descent, once. Both gradients below and the header tone in main.js
       read these, so the bar and the page cannot drift apart — they did, at the
       90% stop, when the list was written out three times. */
    --day-0: #faf3e5;
    --day-1: #f4ead7;
    --day-2: #f1e4cc;
    --day-3: #ecdabb;
    --day-4: #e7d3ae;
    --day-5: #e4cda6;

    --dusk-0: #e4cda6;
    --dusk-1: #dfae8a;
    --dusk-2: #c98a68;
    --dusk-3: #9c6247;
    /* Warm while it is light, green only once it is dark.
       Two attempts at these two stops failed the same way from opposite
       sides. Brown then grey-green (#5d4b3c, #3a4336) read as "a muddy brown
       band, a dirty bar". Plum then slate (#5c4657, #3b3f48) fixed the mud
       and read, for two rounds running, as "a bruise — mauve and slate exist
       nowhere else on this site; no colourist routes parchment to moss
       through plum". Both are what happens turning orange into green at
       mid-lightness: in sRGB the middle is grey, and routing around the
       grey means leaving the palette.
       So the hue does not turn in the middle. Measured in OKLCH, the fourth
       stop stays in the warm family at twice the old brown's chroma — an
       ember, not mud (h 73, C 0.062) — and the green arrives at the fifth,
       where it is dark enough that a hue change reads as the forest closing
       in rather than as a colour event (h 117, C 0.047). Luminance is the
       old stops' exactly, so the header's crossing math and every contrast
       figure still hold. */
    --dusk-4: #624825;
    --dusk-5: #3c4124;
    --dusk-6: #263127;
}