Can this be done with css?

Question

css

Hello!
There are two blocks

<div class="block1"></div>
<div class="block2"></div>

The task is. so that when hovering over one block, for example, change the color of another. Is it possible to do this with css or less? And if possible, please tell me how.

Answer 1

<div class="a">Div A</div>
<div class="b">Div B</div>

.a:hover + .b { /* .a:hover ~ .b - если между элементами есть другие элементы */
    background: #007ffa;
}