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<%# Markup for the scrollspy (table-of-contents scroll tracking) demo.
    stimeo--scrollspy watches the sections with IntersectionObserver and marks the one whose
    top edge sits closest to the trigger line: offset px (20 here) below the top of the
    scroll root, which is the .scrollspy-demo__content container rather than the viewport.
    Intersecting sections win; when none intersects, the closest tracked section keeps the
    highlight, so the table of contents never goes blank. The library sets
    aria-current="location" on the matching link and takes only that value back from the
    others, so an aria-current you set yourself survives. %>
<div class="scrollspy-demo">
  <nav
    class="scrollspy-demo__nav"
    data-controller="stimeo--scrollspy"
    data-stimeo--scrollspy-offset-value="20"
    data-stimeo--scrollspy-root-selector-value=".scrollspy-demo__content"
    aria-label="<%= t("components.scrollspy.demo.title") %>"
  >
    <div class="scrollspy-demo__nav-title"><%= t("components.scrollspy.demo.title") %></div>
    <a
      class="scrollspy-demo__link"
      href="#toc-intro"
      data-stimeo--scrollspy-target="link"
      data-action="click->stimeo--scrollspy#scrollTo"
    >
      <%= t("components.scrollspy.demo.intro_title") %>
    </a>
    <a
      class="scrollspy-demo__link"
      href="#toc-usage"
      data-stimeo--scrollspy-target="link"
      data-action="click->stimeo--scrollspy#scrollTo"
    >
      <%= t("components.scrollspy.demo.usage_title") %>
    </a>
    <a
      class="scrollspy-demo__link"
      href="#toc-api"
      data-stimeo--scrollspy-target="link"
      data-action="click->stimeo--scrollspy#scrollTo"
    >
      <%= t("components.scrollspy.demo.api_title") %>
    </a>
  </nav>

  <%# The content area scrolls but holds no focusable element of its own, so it needs an
      explicit tab stop or keyboard-only users cannot scroll it (WCAG 2.1.1; Safari does not
      make overflow containers implicitly focusable). role="region" is safe to add here
      because the label below gives it an accessible name. %>
  <div
    class="scrollspy-demo__content"
    tabindex="0"
    role="region"
    aria-label="<%= t("components.scrollspy.demo.viewport_label") %>"
  >
    <section id="toc-intro" class="scrollspy-demo__section">
      <h2><%= t("components.scrollspy.demo.intro_title") %></h2>
      <p><%= t("components.scrollspy.demo.intro_body") %></p>
      <div class="scrollspy-demo__spacer"></div>
    </section>

    <section id="toc-usage" class="scrollspy-demo__section">
      <h2><%= t("components.scrollspy.demo.usage_title") %></h2>
      <p><%= t("components.scrollspy.demo.usage_body") %></p>
      <div class="scrollspy-demo__spacer"></div>
    </section>

    <section id="toc-api" class="scrollspy-demo__section">
      <h2><%= t("components.scrollspy.demo.api_title") %></h2>
      <p><%= t("components.scrollspy.demo.api_body") %></p>
      <div class="scrollspy-demo__spacer"></div>
    </section>
  </div>
</div>

/*
 * Presentation-only styles for the scrollspy demo.
 * The active link is styled via aria-current="location" (set by the library).
 */

.scrollspy-demo {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 2rem;
  width: 100%;
  height: 400px;
  background: var(--surface-card);
  border: 1px solid var(--border-default);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.05);
}

.scrollspy-demo__nav {
  display: flex;
  flex-direction: column;
  padding: 1.5rem;
  background: var(--surface-subtle);
  border-right: 1px solid var(--border-default);
  gap: 0.5rem;
}

.scrollspy-demo__nav-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: 0.75rem;
  letter-spacing: 0.05em;
}

.scrollspy-demo__link {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  text-decoration: none;
  padding: 0.375rem 0.75rem;
  border-left: 2px solid transparent;
  transition: all 0.15s ease;
  border-radius: 0 4px 4px 0;
}

.scrollspy-demo__link:hover {
  color: var(--fg);
  background: var(--surface-subtle);
}

.scrollspy-demo__link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* Active state attached by the script (aria-current). */
.scrollspy-demo__link[aria-current="location"] {
  color: var(--accent-700);
  font-weight: 600;
  border-left-color: var(--accent);
  background: rgba(var(--accent-rgb), 0.05);
}

/* The scrolling content area.
   Deliberately no `scroll-behavior`: scrollTo passes "smooth" normally and
   "instant" under prefers-reduced-motion, so the library owns both paths. */
.scrollspy-demo__content {
  overflow-y: scroll;
  padding: 1.5rem;
}

.scrollspy-demo__section {
  padding-bottom: 1rem;
}

.scrollspy-demo__section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--fg);
  margin-top: 0;
  margin-bottom: 0.75rem;
}

.scrollspy-demo__section p {
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--color-text-muted);
  margin: 0;
}

.scrollspy-demo__spacer {
  height: 200px;
}