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HTML

CSS

CSS Base

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JavaScript

Babel includes JSX processing.

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HTML

              
                <nav>
    <a class="nav-item is-active">
        <!--
            Always render the text bold, but hide it visually and for
            assistive technology.
            This causes the `nav-item` to take up the width that it has
            in its active state.
        -->
        <span style="visibility: hidden; font-weight: bold;">Home</span>
        <!--
            Render a visible label, using absolute positioning and flex
            to position it in the center of the nav-item element.
            This label will change `font-weight` depending on its
            active-state but won't affect layout because it's
            `position: absolute;` It will also never overflow because
            the `nav-item` container already has the largest possible
            width.
        -->
        <span class="label">Home</span>
    </a>
    <a class="nav-item">
        <span style="visibility: hidden; font-weight: bold;">Projects</span>
        <span class="label">Projects</span>
    </a>
    <a class="nav-item">
        <span style="visibility: hidden; font-weight: bold;">Blog</span>
        <span class="label">Blog</span>
    </a>
</nav>
              
            
!

CSS

              
                .nav-item {  
  font-weight: normal;
  position: relative;
}
.nav-item.is-active {
  font-weight: bold;
  background: #ccc;
}

.nav-item .label {
  position: absolute;
  top: 0;
  right: 0;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 100%;

  display: inline-flex;
  align-items: center;
  justify-content: center;
}











* {
  margin: 0;
  padding: 0;
}

html, body {
  height: 100%;
}

body {
  font-size: 4rem;
  display: flex;
  align-items: center;
  justify-content: center;
}
.nav-item {
  font-family: sans-serif;
  cursor: pointer;
  display: inline-block;
  padding: 20px;
}
              
            
!

JS

              
                // A little bit of JavaScript to make
// the items clickable
const anchors = Array.from(document.querySelectorAll('a'))

anchors.forEach(a => {
  a.addEventListener('click', function(e) {
    anchors.forEach(a => {
      a.classList.remove('is-active')
    })

    e.currentTarget.classList.add('is-active')
  })  
})

              
            
!
999px

Console