html - Create linear gradient border for top and bottom edges only? - Stack Overflow
Adam Argyle on Twitter: "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 ) ;
html - CSS3 linear gradient for top and bottom of element - Stack Overflow
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