Sidebar

Ion’s Sidebar override acts as a wrapper for the SidebarSublist component, which does the actual heavy lifting, like allowing you to use icons.

Sidebar.astro

---
import type { Props } from '@astrojs/starlight/props';

import MobileMenuFooter from 'virtual:starlight/components/MobileMenuFooter';
import SidebarSublist from 'starlight-ion-theme/components/SidebarSublist.astro';

const { sidebar } = Astro.locals.starlightRoute;
---

<SidebarSublist sublist={sidebar as any} nestedCount={0} />
<div class="md:sl-hidden">
  <MobileMenuFooter {...Astro.props} />
</div>

<style is:global>
  /* Hide markers for summaries (should be hidden by default, but showed again when changing stuff) */
  summary::marker,
  summary::-webkit-details-marker {
    display: none !important;
    background-image: none !important;
    -webkit-appearance: none !important;
  }

  summary.hidden {
    display: none;
  }

  /* Make sure links only have the width they need in the sidebar */
  .sidebar a {
    width: fit-content;
    transition: all 0.1s ease;
  }

  /* Make sure mobile links fill the entire space, not just fit the content */
  nav[aria-labelledby="starlight__on-this-page--mobile"] a {
    width: 100%;
  }

  /*
    This assumes that you will always have a top-level index file / file with the same name if there are subpaths,
    so it moves the upmost nested child to the left
  */
  li.nested:first-of-type {
    position: relative;
    right: 1rem;
  }

  /* Hide all non-active nested children */
  li.nested:not(:first-of-type):not(.active) {
    display: none;
  }

  /*
    If a child is active, show all adjacent children (by checking if the upmost child has an adjacent active li element)
  */
  li.nested:first-of-type:has(~ li.nested.active) ~ li.nested {
    display: block;
  }

  /* Show all adjacent children if an element is active  */
  li.nested.active ~ li.nested {
    display: block;
  }

  li.nested.active.has-icon ~ li.nested {
    /* Icon width */
    left: 14px;
    position: relative;
  }

  /* Make sure nesting works over multiple subpaths */
  li.nested:first-of-type:has(~ li.nested li.nested.active) ~ li.nested {
    display: block;
  }
</style>