IT appears to me that radial gradients in figma and the browser are rendered differently - or alternatively there is something wrong with the css parameters figma spits out.
Have a look at the following screenshot:
This is a 272x56 rectangle, filled by a gradient.
In figma defined like this:
which in dev-mode spits out the code:
background: radial-gradient(183.69% 86.67% at 30.59% 81.58%, #FFF 0%, rgba(255, 255, 255, 0.00) 100%);
The that radial gradient in the web version clearly looks like it has a very different aspect-ratio (a lot wider, while in figma it appears almost circular)