Why CSS Never Matches Figma: Browser vs Canvas Pipelines

Open any Figma file. Look at those perfectly smooth corners, the glass blur with real depth, the stroke that sits cleanly inside the element without touching the spacing. Now build it in CSS. It’s close. But something is always slightly off . The corners feel harder. The blur is flat. The border is eating into your padding. You’ve probably blamed yourself: wrong tool version, wrong browser, not enough CSS tricks. The real reason is simpler: Figma and your browser are two different rendering engines running different math. Some things Figma draws don’t exist in CSS yet. Some things look the same but work differently under the hood. This post breaks down how each engine works, where they diverge, and what that means for every design-to-code handoff. How Chrome turns CSS into pixels When you write CSS and open it in Chrome, six things happen in sequence for every frame and every element. 1. Parse Chrome reads your HTML and builds the DOM (a tree of every element). In parallel it reads CSS