[Fix:#32787] Gradient backgrounds should be set with background-image instead of background

[devanshijoshi9]

What?

This PR changes the gradient background to background-image.

Why?

Because background affects other properties like background-attachment, background-clip, background-color etc. So instead of just using background we can specify our need.

How?

• Use background-image instead of background, we can resolve this.

Fix: #32787

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