How to fix the opacity bug in IE9?

Question

css

Help solve the problem: when hovering over an element, some elements change their opacity property from 0 to 1 in it. Let me remind you that initially these elements have opacity = 0, but when you hover over the element (their parent), the opacity property = 1 for these elements (children).

.ctrl {
    margin-top: -20px;
    height: 40px;
    width: 20px;

    #gradient > .vertical(@white, #F3F4F5);
    .opacity(0);
  }

.category {
  &:hover {
    .ctrl {
      .opacity(1);
    }
  }
}

Answer 1

In short, if I understood everything correctly, then you need a pie))))))
css3pie.com