How To Use Gradients in Flutter with BoxDecoration and GradientAppBar | DigitalOcean
CSS Linear Gradients - ElseBazaar
Twitter 上的Adam Argyle:"Opposing corner radial gradients look softer than angled linear gradients: #CSS background-image: radial-gradient( circle at top right, cyan, transparent ), radial-gradient( circle at bottom left, deeppink, transparent ) ;