15 min read CSS , Coding , Techniques Seventy percent of websites still fail basic WCAG contrast checks in 2025. After years of design system tooling, accessibility linters, and JavaScript libraries, nothing moved the needle. We didn’t need better libraries. We needed better CSS. contrast-color() is that better CSS. The HTTP Archive Web Almanac has been tracking color contrast failures for years. The numbers have barely moved. After half a decade of design system tooling, accessibility linters, and entire JavaScript libraries dedicated to computing readable text colors, 70% of websites still fail basic WCAG contrast checks in 2025 . The WebAIM Million paints an even grimmer picture — 83.9% of homepages flagged for low contrast text in 2026, up from 79.1% in 2025. The rate improves by maybe a few percentage points per year on one benchmark and actually gets worse on another. That’s not progress — that’s proof that relying on runtime JavaScript for something this fundamental doesn’t scale across the open web.…