我的 CSS 悬停代码在侧边导航栏中的确切错误是什么？

Question

**在我的社交媒体图标项目中，我尝试使用不透明度 0 隐藏我的文本。当用户将鼠标悬停在我的标签或图标上时，将显示文本。但我的悬停过渡不起作用。请首先尝试在我的 CSS in .icon.Please 中使用 opacity 1 来解决我的悬停问题。我不明白这是什么错误

:root {
  --darkblu: #2c3e50;
  --linkclr: #fff;
  --lightblue: lightblue;
  --violet: violet;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.side_nav {
  background-color: var(--darkblu);
  height: 100vh;
  width: 50px;
  position: fixed;
  display: flex;
  flex-flow: column nowrap;
  justify-content: flex-start;
  align-items: center;
  /* overflow: hidden; */
}

.icon_holder {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

.icon {
  width: 100%;
  height: 100%;
  /* background-color: var(--lightblue); */
}

.side_nav .icon_holder .icon a {
  text-decoration: none;
  color: var(--linkclr);
  font-size: 80%;
  /* width: 100%;
        height: 100%; */
  display: inline-block;
  margin: 20px 0px;
  padding: 10px;
}

.icon_holder span {
  position: absolute;
  left: 100%;
  width: 100px;
  background-color: var(--violet);
  margin: 0px 24px;
  padding: 5px;
  text-align: center;
  border-radius: 4px;
  opacity: 0;
}

.icon_holder span::before {
  content: '';
  position: absolute;
  height: 10px;
  width: 10px;
  transform: rotate(45deg);
  background-color: var(--violet);
  top: 35%;
  left: -5%;
}

.icon_holder:nth-child(1):hover .icon_holder span {
  opacity: 1;
}

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="style.css">
  <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.15.4/css/all.css" integrity="sha384-DyZ88mC6Up2uqS4h/KRgHuoeGwBcD4Ng9SiP4dIRy0EXTlnuz47vAwmeGwVChigm" crossorigin="anonymous">
</head>

<body>
  <div class="side_nav">
    <div class="icon_holder">
      <div class="icon"><a href="#"><i class="fas fa-home"></i></a></div>
      <span>Home</span>
    </div>
    <div class="icon_holder">
      <div class="icon"><a href="#"><i class="fas fa-blog"></i></a></div>
      <span>Blog</span>
    </div>
    <div class="icon_holder">
      <div class="icon"><a href="#"><i class="fas fa-question"></i></a></div>
      <span>About Us</span>
    </div>
    <div class="icon_holder">
      <div class="icon"><a href="#"><i class="fab fa-whatsapp"></i></a></div>
      <span>Whatsapp</span>
    </div>
    <div class="icon_holder">
      <div class="icon"><a href="#"><i class="fas fa-user"></i></a></div>
      <span>User Access</span>
    </div>
  </div>
</body>

</html>

Answer 1

使用这个：

.icon_holder span {
    position: absolute;
    left: 100%;
    width: 100px;
    background-color: var(--violet);
    margin: 0px 24px;
    padding: 5px;
    text-align: center;
    border-radius: 4px;
    opacity: 0;
    transition: 500ms all;//add transition
}

.icon_holder:hover span{
    opacity: 1;
}

我的 CSS 悬停代码在侧边导航栏中的确切错误是什么？

What's the exact bug with my CSS hovering code in side nav bar?

html

css

hover