<div class="topbar">
   <div class="part1">
    <a href="#">link #1</a>
    <a href="#">link #2</a>
    <a href="#">link #3</a>
  </div>
  
  <div class="part2">
    <a href="#">link #4</a>
    <a href="#">link #5</a>
  </div>
  
  <div class="part3">
    <a href="#">link #6</a>    
  </div>

</div>
.topbar {
  display: flex;
}

.topbar > div {
  display: contents;
}

.topbar a {
  padding: 0.2rem;  
  flex: 1;
}

External CSS

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External JavaScript

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