Thread:Project:Support desk/Custom hover to change font color doesn't work

I'm trying to create a spoiler text hide/reveal thing. My CSS changes the text's color and the background to black by default, but the :hover part isn't working and I don't know why. The :hover elements of links work as they should. I appreciate any help!

/* Spoiler hover reveal */

.spoiler {

font-color: #000000;

background-color: #000000;

}

.spoiler:hover {

font-color: #ffffff;

background-color: #000000;

}

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