How to get a CSS filter snippet for color-blindness simulation

1. Run with no input

   This tool takes no input fields — just press Run. It returns a paste-ready CSS snippet that you can drop into a stylesheet (no other configuration).

2. What you get

   Result is a single `css` field with three filter classes: `.cb-protanopia`, `.cb-deuteranopia`, `.cb-tritanopia`. Each uses a SVG `feColorMatrix` matrix that approximates one type of color-vision deficiency.

3. Using it

   Add the relevant class to `body` (or a wrapper) to preview your design as roughly 8% of men with red-green color blindness, or a much smaller share with blue-yellow, would see it. Toggle the class from devtools — no rebuild needed.

4. Caveats

   These are linear approximations; real color vision is more nuanced. Tools like Sim Daltonism (macOS) or Coblis use better models. Always pair this preview with WCAG contrast checks (use wcag-contrast-checker-online) — color shouldn't carry information alone.