Answers for "hover an element and effect another element"

css affect other elements on hover

#container:hover ~ #cube { background-color: yellow; }

css hover change another element

#a:hover ~ #b {
    background: #ccc
}

<div id="a">Div A</div>
<div>random other elements</div>
<div>random other elements</div>
<div>random other elements</div>
<div id="b">Div B</div>