pinafore/src/routes/_components/TabSet.html

<nav aria-label={label} class={className}>
  <ul>
    {#each tabs as tab (tab.name)}
    <li class="{currentTabName === tab.name ? 'current' : 'not-current'}">
      <a aria-label="{tab.label} { currentTabName === tab.name ? '(Current)' : ''}"
         href={tab.href}
         rel="prefetch">
        {tab.label}
      </a>
    </li>
    {/each}
  </ul>
</nav>
<style>
  li {
    flex: 1;
    text-align: center;
  }

  /* reset */
  ul, li {
    margin: 0;
    padding: 0;
  }

  ul {
    list-style: none;
    display: flex;
    margin: 0;
    box-sizing: border-box;
  }

  li {
    border: 1px solid var(--main-border);
    box-sizing: border-box;
    display: flex;
    justify-content: center;
    align-items: center;
    border-top-left-radius: 7px;
    border-top-right-radius: 7px;
    background: var(--tab-bg);
    border-left: none;
  }

  li:last-child {
    border-right: none;
  }

  li:hover {
    background: var(--button-bg-hover);
  }

  li.not-current {
    background: var(--tab-bg-non-selected);
  }

  li.current {
    border-bottom: none;
  }

  li.current:hover {
    background: var(--tab-bg-hover);
  }

  li.not-current:hover {
    background: var(--tab-bg-hover-non-selected);
  }

  li:active {
    background: var(--tab-bg-active);
  }

  a {
    padding: 7px 10px;
    color: var(--body-text-color);
    font-size: 1.1em;
    flex: 1;
  }

  a:hover {
    text-decoration: none;
  }
</style>
<script>
  export default {
    data: () => ({
      className: ''
    })
  }
</script>