- demo iframe: scrolling=no (the bridge auto-sizes; a scrollable iframe trapped the wheel) + content-box so the bridge height is the viewport - figures: svgNaturalWidth hug + center (w-fit max-w-full mx-auto), full-width fallback for viewBox-only svgs - fullscreen: MermaidOverlay figure mode (raw svg, white stage, invert carried); openFigure context; figureFocus rides the mermaid Esc layer - downloads: figure.svg + <slug>.html (raw pre-bridge), shared download.ts - invert: manual ContrastIcon toggle on both cards — invert(1) hue-rotate(180deg) on the white-bearing element, default off, no detection, no theme wiring (owner rulings 2026-10-07) 1433 tests green; live smoke passed (hug/center measured, filters verified, downloads fired, Esc closed; wheel-chaining structurally sound)