Customize scroll to top button

Hi there

I found some css to change color of the scroll to top button at
https://docs.generatepress.com/article/back-to-top-button/#changing-the-color

and some other css at

https://docs.generatepress.com/article/back-to-top-button/#other-styles

However it does not change the color. For trying out the code now is:

`.generate-back-to-top,
.generate-back-to-top:visited {
background-color: rgba( 225, 0, 0, 0.4 ); /* rgba or hex */
color: #FFFFFF;
}

/* the button when you hover/click it */

.generate-back-to-top:hover,
.generate-back-to-top:focus {
background-color: rgba( 0, 225, 0, 0.6 ); /* rgba or hex */
color: #FFFFFF;
}

Any idea why the button still is grey instead of red or green?

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