nx_media_theme.nx

nx_media_theme.nx -- SOVEREIGN READING-SURFACE THEME ENGINE for /gallery + /library. Closes the TEN media.matrix rows that all name this organ (operator buy-off 2026-07-14: harsh plain white, no dark theme, clunky): light+dark theme, sunlight/outdoor readability, ambient adaptation, mobile legibility, anti-glare surface, warm night shift, flicker/refresh comfort, paper-like feel, reading typography, blue-light reduction. NOT A STUB. media.matrix's own axis says a symbol on disk is NECESSARY-NOT-SUFFICIENT, so this organ is built to be MEASURED, not greppable: every palette is a token row that mt_contrast() scores through the estate's WCAG kernel, and every claim it makes is a number its gate can refuse. DRY (rule 15) -- this organ INVENTS NOTHING THE ESTATE ALREADY OWNS: * WCAG math -> nx_uiq_color.nx (uiq_parse_color / uiq_ratio100 / uiq_lum). That file's header declares itself THE ONE WCAG 2.x relative-luminance + contrast-ratio implementation and carries a D001 migrate-on-touch note. A second luminance kernel here would be the exact duplication that note exists to prevent -- and would have been the FOURTH copy in this estate. * data format + parser + safety -> nx_brand_tokens.nx (bt_slice_eq / bt_value_safe / bt_app / bt_emit_root_buf). * mode vocabulary + hex values -> nx_night_grade.nx 6-theme SSOT (migrated from night_themes.tsv). light/sepia/ dark/night bg+fg are BYTE-FAITHFUL to it, so its already-measured blue-emission assertions still hold here instead of new ones being asserted. * override idiom -> data-theme, matching nishi_ds.css and nx_papers_index.nx. Not a new attribute. DATA-DRIVEN (rule 11): every palette value, threshold and floor is a named const or a row in MT_PALETTE_S. OVERRIDE SEMANTICS -- the user wins in BOTH directions. The OS default rides prefers-color-scheme, but it is scoped :root:not([data-theme]), so once a user picks a mode the media query CANNOT win. A bare @media block cannot express OS-dark + user-picks-light. HONEST LIMITS -- stated, not papered over: * Reflective/paper-like and matte/anti-glare are PHYSICAL display properties the web cannot set. This ships the controllable proxy: a paper palette and a capped peak luminance (sepia bg #f4ecd8, not #ffffff). It does not make glass matte. * Flicker-free is a panel property (PWM / e-ink). The controllable parts are motion and the first-paint flash; both are handled (prefers-reduced-motion, and color-scheme so the UA paints the correct base colour BEFORE first paint instead of flashing white). * Ambient-light auto-adaptation is DELEGATED to the OS signal. A real AmbientLightSensor lane is NOT implemented and is NOT claimed -- that matrix row stays _ABSENT_. Usage: nx_media_theme [--css | --table | --contrast <mode> | --kat] (default --css)