Show Flyout Menu using mouseover event

November 7, 2022

I have a flyout menu which I am trying to toggle using the mouseover event, however it doesn’t seem to work as intended. I tried using a hover event with CSS by targeting the div like this: .hero-list-block a:hover + .flyout-menu

However this didn’t work. Any suggestions on how I can fix this/improve this? Thanks

const flyoutLink = document.querySelector('.flyout-link');
const flyoutMenu = document.querySelector('.flyout-menu');

flyoutLink.addEventListener('mouseover', () => {
  flyoutMenu.classList.toggle('.flyout-menu-show');
})

.grid-hero-wrapper {
  grid-template-columns: 100px 1fr;
  gap: 15px;
  margin-top: 15px;
  display: grid;
}

.hero-categories-block {
  background: #fff;
  border: 1px solid #28282b;
}

.hero-categories-list {
  display: flex;
  flex-direction: column;
  padding: 5px 0;
  height: 100%;
}

.flyout-menu-show {
  opacity: 1;
  visibility: visible;
}

.flyout-menu {
  background: #fff;
  border: 1px solid #28282b;
  position: absolute;
  top: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  visibility: hidden;
  position: absolute;
  z-index: 999;
}

.hero-categories-list a {
  display: flex;
  align-items: center;
  flex-grow: 1;
  font-size: 0.75rem;
  height: 22px;
  color: #333;
}

.hero-slider-block {
  position: relative;
}

<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" rel="stylesheet" />
<div class="grid-hero-wrapper">
  <div class="hero-categories-block">
    <div class="hero-categories-list">
      <a href="#" class="flyout-link">Flyout</a>
      <a href="#" class="flyout-link">Flyout</a>
    </div>
  </div>
  <div class="hero-slider-block">
    <div id="carouselExampleSlidesOnly" class="carousel slide" data-bs-ride="carousel">
      <div class="carousel-inner">
        <div class="carousel-item active hero-slider-img">
          <img src="https://images.unsplash.com/photo-1507525428034-b723cf961d3e?ixlib=rb-4.0.3&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=1173&q=80" class="d-block w-100">
        </div>
      </div>
    </div>
    <div class="flyout-menu">
      <h1>This is my flyout menu</h1>
    </div>
  </div>
</div>

>Solution :

This is not working because of the specificity of your css selectors.

.flyout-menu-show selector is declared before .flyout-menu selector and they got the same specificity. So only the latest applies to your element.

change

.flyout-menu-show {
  opacity: 1;
  visibility: visible;
}

.flyout-menu.flyout-menu-show {
  opacity: 1;
  visibility: visible;
}

This will create a selector with higher specificity, and it will be applied properly :). Working codepen of your sample: https://codepen.io/aSH-uncover/pen/PoaboWo

probably worth reading this page too : https://developer.mozilla.org/en-US/docs/Web/CSS/Specificity