CSS Child element animation when parent element hovers: Tips for implementing the transition between text and lines

1. Line Animation: A dynamic underscore or decorative line appears below or above the link text.
2. Text animation: The link text itself moves slightly upward.

Core Solution: Separation of Responsibilities

The key to solving this problem lies in "separation of responsibilities". We assign different animation effects to the most appropriate elements to be responsible for:

Code implementation and parsing

The following is the CSS code optimized according to the above strategy, with detailed analysis.

The HTML structure remains the same:

 <div class="'container'">
  <main class="'main'">
    <div class="'nav'">
      <div class="'navIcon'">
        <img  src="/static/imghw/default1.png" data-src="https://picsum.photos/40" class="lazy" height="{40}"    style="max-width:90%" alt="CSS Child element animation when parent element hovers: Tips for implementing the transition between text and lines" >
      </div>
      <ul class="'snip1168'">
        <li class="'current'"><a href="#" data-hover="Work">Work</a></li>
        <li><a href="#" data-hover="Recs">Recs</a></li>
        <li><a href="#" data-hover="Say Hi">Say Hi</a></li>
      </ul>
    </div>
  </main>
</div>

Optimized CSS code:

 /* The general style remains unchanged*/
html, body {
  padding: 0;
  margin: 0;
  font-family: "sequel-sans-roman", -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Oxygen, Ubuntu, Cantarell, Fira Sans, Droid Sans, Helvetica Neue, sans-serif;
}

.container {
  padding: 0 2rem;
}

.main {
  min-height: 100vh;
  padding: 4rem 0;
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

a {
  color: inherit;
  text-decoration: none;
}

* {
  box-sizing: border-box;
}

.navIcon {
  display: inline-block;
  flex-grow: 1;
}

.nav {
  display: flex;
  justify-content: space-between;
  width: 100%;
  margin-top: 2.4em; /* Coordination and link distance*/
}

.snip1168 {
  text-align: center;
  text-transform: uppercase;
}

.snip1168 * {
  box-sizing: border-box;
}

/* Modify the li element*/
.snip1168 li {
  display: inline-block; /* Make sure li can set width and position pseudo-elements*/
  list-style: none;
  margin: 0 1.5em;
  padding: 2.4em 0 0.5em; /* The padding originally on a is moved to li */
  color: rgba(0, 0, 0, 1);
  position: relative; /* Provides positioning context for pseudo-elements*/
  text-decoration: none;
  /* background: pink; /* for debugging, you can delete */ */
}

/* Move line pseudo-element style from a to li */
.snip1168 li:before,
.snip1168 li:after {
  position: absolute;
  -webkit-transition: all 0.35s ease;
  transition: all 0.35s ease;
}

.snip1168 li:before {
  top: 0;
  display: block; /* Pseudo-elements usually require block or inline-block to set width and height*/
  height: 3px;
  width: 0%;
  content: "";
  background-color: black;
}

/* li triggers line animation when hovering*/
.snip1168 li:hover:before,
.snip1168 .current li:before { /* The activation status is also applied*/
  opacity: 1;
  width: 100%;
}

/* Another pseudo-element (if present) */
.snip1168 li:hover:after,
.snip1168 .current li:after {
  max-width: 100%;
}

.mainText {
  text-transform: uppercase;
  font-size: 1.1rem;
}

/* Add text bit movement to element a*/
.snip1168 li a {
  transition: transform ease 400ms; /* Define the transition effect of transform animation*/
  transform: translate(0, 0); /* Initial state, text does not shift*/
  display: inline-block; /* Ensure that the transform attribute takes effect*/
}

/* When li hovering, the element a moves upward*/
.snip1168 li:hover a {
  transform: translate(0, -10px); /* The text moves upward by 10px */
}

Key code point analysis:

Notes and best practices