Change hover color TOC

Love the plugin but how do I code the CSS so that the title text changes color when hovered? I tried this:

.simpletoc {
padding: 1em 2em;
background: #FFC600;
}
a:hover {
color: black
text-decoration: underline;
}

but instead I get the same white color text over a light grey background instead of the title text going to black. Appreciate the help in coding. Tried chatgpt but the above was what I got that isn’t working.

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