Declarative HDR on SVG vectors — color(rec2100-*) (with SDR fallback)

Each bar: style="fill:#fff; fill:color(rec2100-pq …)". If the browser supports CSS Color HDR, the higher bars render brighter than SDR white (203); if not, they all stay plain white. No canvas, no JS.

203 (SDR / HDR reference white)400 nits700 nits1000 nits2000 nits4000 nits10000 nits · peak PQ(1,1,1) HLG 1,1,1 — relative display peak (adaptive) HDR-lifted viridis as a vector gradient (top ≈6× SDR white): Unsupported → falls back to plain white / SDR viridis. If the high-nit & HLG bars look BRIGHTER than the 203 bar, declarative HDR color() works in this browser.