Build a CSS gradient and copy the exact declaration. Angles follow the CSS specification, where 0deg points up and angles turn clockwise.
Start from
background-image: linear-gradient(135deg, #1e3a8a 0%, #7c3aed 55%, #f472b6 100%);1 layer, painted in order — the first sits on top of the ones below it.
A CSS gradient is a generated image, not a colour, which is why it belongs in background-image rather than background-color. The angle is the part people get wrong most often: in CSS, 0deg points upward and angles turn clockwise, so 90deg runs left to right. This editor takes as many colour stops as you need, lets you reorder them, and stacks several gradients into one declaration — the way mesh backgrounds are built. Everything is assembled in your browser and nothing is sent anywhere.
linear-gradient([ <angle> | to <side-or-corner> ]?, <color-stop-list>)
The grammar comes straight from the CSS Images specification. Each colour stop is a colour followed by an optional position, and percentages resolve against the gradient line, with 0% at the start and 100% at the end.
Source: W3C CSS Images Module Level 3 — <linear-gradient()> grammar and gradient line
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