/* CLIENT TOKEN LAYER — loaded on every page, before the page-type stylesheet.
   It exists so a token the board defined on only SOME of its pages is defined
   ONCE for all of them.

   ⚠ BOARD DEFECT, found at port (2026-09-23): `--photo` is defined on
   :root in the Home and About stylesheets, but `back-pain.html`,
   `spinal-decompression.html` and `404.html` USE `filter:var(--photo)` without
   ever defining it. On those three pages the declaration resolved to nothing
   and the hero photography rendered at full saturation, off the board's
   monochrome treatment. Defining it here fixes all three and cannot drift,
   because the page stylesheets that DO define it simply re-declare the same
   value later in the cascade. */
:root {
  --photo: grayscale(.85) sepia(.06) contrast(1.04) brightness(.96);
}