fix(www): make search placeholder full visible

[parammittal16]

Description

Fixes the visibility of the search placeholder on home and other pages.

Before

After

Related Issues

Fixes #9694

[parammittal16]

@KyleAMathews @DSchau Plz review this.

[DSchau]

Not able to replicate the issue, but it seems that others in the original issue are able to, so we can merge this.

Thanks!

[gatsbot]

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Thanks again!

[parammittal16]

Thank you So Much @DSchau :)