Bootstrap 5 Expanding Search Bar with Suggestions

<section class="wdw-stage py-4">
  <div class="container" style="max-width:680px">
    <div class="text-center mb-4">
      <span class="wdw-eyebrow">Expanding search</span>
      <h1 class="wdw-heading display-5 mt-1 mb-2">Search the docs</h1>
      <p class="wdw-muted mb-0">A single icon that grows into a full search bar. Hover it, tap it, or press /.</p>
    </div>

    <div class="xs-wrap">
      <div class="d-flex justify-content-center">
        <form class="xs is-open" id="xsearch" role="search" onsubmit="return false">
          <label for="xsInput" class="visually-hidden">Search the docs</label>
          <input id="xsInput" class="xs-input" type="search" value="bu" placeholder="Search docs…" autocomplete="off" role="combobox" aria-controls="xsList" aria-expanded="true" aria-haspopup="listbox" aria-autocomplete="list">
          <kbd class="xs-kbd">/</kbd>
          <button class="xs-btn" type="submit" id="xsBtn" aria-label="Search">
            <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><circle cx="11" cy="11" r="7"/><path d="m20 20-3.5-3.5"/></svg>
          </button>
          <div class="xs-panel" id="xsPanel">
            <div class="xs-label" id="xsLabel">Suggestions</div>
            <ul class="xs-list list-unstyled m-0" id="xsList" role="listbox" aria-labelledby="xsLabel"></ul>
            <p class="xs-empty m-0" id="xsEmpty" hidden></p>
            <div class="xs-foot" aria-hidden="true">
              <span><kbd>↑</kbd> <kbd>↓</kbd> to navigate</span>
              <span><kbd>↵</kbd> to select</span>
              <span class="ms-auto"><kbd>esc</kbd> to close</span>
            </div>
          </div>
        </form>
      </div>
      <p class="text-center small wdw-muted mt-3 mb-0" id="xsStatus" role="status" aria-live="polite"></p>
    </div>
  </div>
</section>

/* Web Designer Wall library style — shared base for every Bootstrap 5 snippet.
   Indigo accent, Plus Jakarta Sans, soft cards, pill buttons. Works in light and dark. */
@import url("https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap");

:root,
[data-bs-theme="light"] {
  --wdw-font: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --bs-body-font-family: var(--wdw-font);
  --bs-primary: #4f46e5;
  --bs-primary-rgb: 79, 70, 229;
  --bs-primary-text-emphasis: #3730a3;
  --bs-primary-bg-subtle: #eef2ff;
  --bs-primary-border-subtle: #c7d2fe;
  --bs-link-color: #4f46e5;
  --bs-link-color-rgb: 79, 70, 229;
  --bs-link-hover-color: #4338ca;
  --bs-link-hover-color-rgb: 67, 56, 202;
  --bs-focus-ring-color: rgba(79, 70, 229, 0.25);
  --bs-border-radius: 0.75rem;
  --bs-border-radius-lg: 1rem;
  --bs-border-radius-xl: 1.25rem;
  --wdw-radius-card: 1.25rem;
  --wdw-shadow: 0 1px 2px rgba(16, 24, 40, 0.05), 0 16px 40px -16px rgba(16, 24, 40, 0.22);
  --wdw-shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06), 0 4px 12px -4px rgba(16, 24, 40, 0.12);
  --wdw-stage: #f5f6fb;
}

[data-bs-theme="dark"] {
  --bs-primary: #818cf8;
  --bs-primary-rgb: 129, 140, 248;
  --bs-primary-text-emphasis: #c7d2fe;
  --bs-primary-bg-subtle: rgba(129, 140, 248, 0.14);
  --bs-primary-border-subtle: rgba(129, 140, 248, 0.35);
  --bs-link-color: #a5b4fc;
  --bs-link-color-rgb: 165, 180, 252;
  --bs-link-hover-color: #c7d2fe;
  --bs-link-hover-color-rgb: 199, 210, 254;
  --bs-focus-ring-color: rgba(129, 140, 248, 0.35);
  --wdw-shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 16px 40px -16px rgba(0, 0, 0, 0.7);
  --wdw-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4), 0 4px 12px -4px rgba(0, 0, 0, 0.5);
  --wdw-stage: #0f1117;
}

body { font-family: var(--wdw-font); -webkit-font-smoothing: antialiased; }

/* Bootstrap compiles its blue into these components; point them at the accent. */
.btn-primary {
  --bs-btn-bg: var(--bs-primary); --bs-btn-border-color: var(--bs-primary);
  --bs-btn-hover-bg: #4338ca; --bs-btn-hover-border-color: #4338ca;
  --bs-btn-active-bg: #3730a3; --bs-btn-active-border-color: #3730a3;
  --bs-btn-disabled-bg: var(--bs-primary); --bs-btn-disabled-border-color: var(--bs-primary);
  --bs-btn-focus-shadow-rgb: var(--bs-primary-rgb);
}
[data-bs-theme="dark"] .btn-primary { --bs-btn-color: #0f1117; --bs-btn-hover-bg: #a5b4fc; --bs-btn-hover-border-color: #a5b4fc; --bs-btn-hover-color: #0f1117; --bs-btn-active-color: #0f1117; }
.btn-outline-primary {
  --bs-btn-color: var(--bs-primary); --bs-btn-border-color: var(--bs-primary);
  --bs-btn-hover-bg: var(--bs-primary); --bs-btn-hover-border-color: var(--bs-primary);
  --bs-btn-active-bg: var(--bs-primary); --bs-btn-active-border-color: var(--bs-primary);
  --bs-btn-focus-shadow-rgb: var(--bs-primary-rgb);
}
.btn { --bs-btn-font-weight: 600; min-height: 44px; display: inline-flex; align-items: center; justify-content: center; gap: .5rem; }
.btn-sm { min-height: 36px; }
.form-control, .form-select { min-height: 44px; border-radius: .75rem; }
.form-control:focus, .form-select:focus, .form-check-input:focus { border-color: rgba(var(--bs-primary-rgb), .6); box-shadow: 0 0 0 .25rem var(--bs-focus-ring-color); }
.form-check-input:checked { background-color: var(--bs-primary); border-color: var(--bs-primary); }
.nav-pills { --bs-nav-pills-link-active-bg: var(--bs-primary); }
.nav { --bs-nav-link-color: var(--bs-secondary-color); --bs-nav-link-hover-color: var(--bs-emphasis-color); }
.pagination { --bs-pagination-active-bg: var(--bs-primary); --bs-pagination-active-border-color: var(--bs-primary); --bs-pagination-color: var(--bs-body-color); --bs-pagination-focus-box-shadow: 0 0 0 .25rem var(--bs-focus-ring-color); }
.progress, .progress-stacked { --bs-progress-bar-bg: var(--bs-primary); }
.list-group { --bs-list-group-active-bg: var(--bs-primary); --bs-list-group-active-border-color: var(--bs-primary); }
.dropdown-menu { --bs-dropdown-link-active-bg: var(--bs-primary); border-radius: .875rem; box-shadow: var(--wdw-shadow-sm); }
.accordion { --bs-accordion-active-bg: var(--bs-primary-bg-subtle); --bs-accordion-active-color: var(--bs-primary-text-emphasis); --bs-accordion-btn-focus-box-shadow: 0 0 0 .25rem var(--bs-focus-ring-color); }
.badge { font-weight: 600; }

/* Library building blocks — use these instead of re-inventing them per snippet. */
.wdw-stage { min-height: 100vh; display: flex; align-items: center; background: var(--wdw-stage); padding-block: 3rem; }
.wdw-card { background: var(--bs-body-bg); border: 1px solid var(--bs-border-color-translucent); border-radius: var(--wdw-radius-card); box-shadow: var(--wdw-shadow); }
.wdw-card-sm { background: var(--bs-body-bg); border: 1px solid var(--bs-border-color-translucent); border-radius: 1rem; box-shadow: var(--wdw-shadow-sm); }
.wdw-aurora { position: relative; color: #fff; background: radial-gradient(60% 55% at 100% 0, #818cf8 0, transparent 70%), radial-gradient(65% 60% at 0 100%, #ec4899 0, transparent 65%), #1e1b4b; }
.wdw-eyebrow { display: inline-block; font-size: .75rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--bs-primary); }
.wdw-heading { font-weight: 800; letter-spacing: -.02em; color: var(--bs-emphasis-color); }
.wdw-muted { color: var(--bs-secondary-color); }
.wdw-icon { width: 2.75rem; height: 2.75rem; flex: none; display: inline-flex; align-items: center; justify-content: center; border-radius: .875rem; background: var(--bs-primary-bg-subtle); color: var(--bs-primary); }

/* Component */
.xs-wrap { min-height: 21rem; }
.xs { position: relative; width: 3.5rem; height: 3.5rem; display: flex; align-items: center; background: var(--bs-body-bg); border: 1px solid var(--bs-border-color-translucent); border-radius: 99px; box-shadow: var(--wdw-shadow-sm); transition: width .45s cubic-bezier(.2,.8,.2,1), box-shadow .3s; }
.xs:hover, .xs:focus-within, .xs.is-open { width: 100%; box-shadow: var(--wdw-shadow); }
.xs:focus-within { border-color: rgba(var(--bs-primary-rgb), .55); box-shadow: 0 0 0 .25rem var(--bs-focus-ring-color), var(--wdw-shadow); }
.xs-input { flex: 1; min-width: 0; width: 100%; height: 100%; border: 0; background: transparent; color: var(--bs-body-color); padding: 0 0 0 1.5rem; font-size: 1rem; outline: 0; opacity: 0; transition: opacity .2s; }
.xs:hover .xs-input, .xs:focus-within .xs-input, .xs.is-open .xs-input { opacity: 1; transition-delay: .15s; }
.xs-input::placeholder { color: var(--bs-secondary-color); }
.xs-input::-webkit-search-cancel-button { display: none; }
kbd { background: var(--bs-tertiary-bg); color: var(--bs-secondary-color); border: 1px solid var(--bs-border-color); font-size: .75rem; padding: .1rem .45rem; border-radius: .4rem; }
.xs > .xs-kbd, .xs > kbd { flex: none; margin-right: .5rem; display: none; }
@media (min-width: 576px) { .xs:hover > kbd, .xs:focus-within > kbd, .xs.is-open > kbd { display: inline-block; } }
.xs-btn { flex: none; width: 2.75rem; height: 2.75rem; margin-right: .3rem; margin-left: auto; border: 0; border-radius: 50%; background: var(--bs-primary); color: #fff; display: inline-flex; align-items: center; justify-content: center; transition: transform .2s, background .2s; }
[data-bs-theme="dark"] .xs-btn { color: #0f1117; }
.xs-btn:hover { transform: scale(1.06); }
.xs-btn:focus-visible { outline: 2px solid var(--bs-primary); outline-offset: 2px; }
.xs-panel { position: absolute; top: calc(100% + .6rem); left: 0; right: 0; padding: .5rem; background: var(--bs-body-bg); border: 1px solid var(--bs-border-color-translucent); border-radius: 1.25rem; box-shadow: var(--wdw-shadow); z-index: 10; }
.xs-panel[hidden], .xs-empty[hidden] { display: none; }
.xs-label { font-size: .7rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--bs-secondary-color); padding: .4rem .75rem .35rem; }
.xs-opt { display: flex; align-items: center; gap: .75rem; padding: .65rem .75rem; border-radius: .75rem; cursor: pointer; color: var(--bs-body-color); min-height: 44px; }
.xs-opt small { margin-left: auto; color: var(--bs-secondary-color); }
.xs-opt svg { flex: none; color: var(--bs-secondary-color); }
.xs-opt:hover { background: var(--bs-tertiary-bg); }
.xs-opt[aria-selected="true"] { background: var(--bs-primary-bg-subtle); box-shadow: inset 0 0 0 2px var(--bs-primary); }
.xs-opt mark { background: none; color: var(--bs-primary); font-weight: 700; padding: 0; }
.xs-empty { padding: .9rem .75rem; color: var(--bs-secondary-color); }
.xs-foot { display: flex; flex-wrap: wrap; gap: .5rem 1rem; align-items: center; margin-top: .4rem; padding: .6rem .75rem .3rem; border-top: 1px solid var(--bs-border-color-translucent); font-size: .75rem; color: var(--bs-secondary-color); }
@media (max-width: 575.98px) { .xs-foot span:last-child { display: none; } .xs-wrap { min-height: 24rem; } }
@media (prefers-reduced-motion: reduce) { .xs, .xs-input { transition: none; } }

(function () {
  const ITEMS = [
    ['Buttons', 'Component'], ['Button groups', 'Component'], ['Build tools', 'Guide'], ['Bundle size', 'Guide'],
    ['Badges', 'Component'], ['Breadcrumb', 'Component'], ['Cards', 'Component'], ['Carousel', 'Component'],
    ['Dropdowns', 'Component'], ['Forms', 'Guide'], ['Grid system', 'Guide'], ['Icons', 'Library'],
    ['Modal', 'Component'], ['Navbar', 'Component'], ['Tooltips', 'Component']
  ];
  const RECENT = [['Modal', 'Component'], ['Grid system', 'Guide'], ['Dark mode', 'Guide']];
  const CLOCK = '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><circle cx="12" cy="12" r="9"/><path d="M12 7v5l3 2"/></svg>';

  function initExpandingSearch() {
    const form = document.getElementById('xsearch');
    if (!form) return;
    const input = form.querySelector('#xsInput');
    const panel = form.querySelector('#xsPanel');
    const label = form.querySelector('#xsLabel');
    const list = form.querySelector('#xsList');
    const empty = form.querySelector('#xsEmpty');
    const status = document.getElementById('xsStatus');
    let active = -1;

    const esc = s => s.replace(/[&<>"]/g, c => ({ '&': '&', '<': '<', '>': '>', '"': '"' }[c]));

    function render(highlightFirst) {
      const q = input.value.trim().toLowerCase();
      const hits = q ? ITEMS.filter(i => i[0].toLowerCase().includes(q)).slice(0, 5) : RECENT;
      label.textContent = q ? 'Suggestions' : 'Recent searches';
      list.innerHTML = hits.map((h, i) => {
        let name = esc(h[0]);
        if (q) {
          const at = h[0].toLowerCase().indexOf(q);
          name = esc(h[0].slice(0, at)) + '<mark>' + esc(h[0].slice(at, at + q.length)) + '</mark>' + esc(h[0].slice(at + q.length));
        }
        return '<li class="xs-opt" role="option" id="xs-o' + i + '" aria-selected="false" data-v="' + esc(h[0]) + '">' + (q ? '' : CLOCK) + '<span>' + name + '</span><small>' + h[1] + '</small></li>';
      }).join('');
      list.hidden = !hits.length;
      empty.hidden = !!hits.length;
      empty.textContent = hits.length ? '' : 'No results for “' + input.value.trim() + '”';
      panel.hidden = false;
      form.classList.add('is-open');
      input.setAttribute('aria-expanded', 'true');
      active = -1;
      input.removeAttribute('aria-activedescendant');
      if (highlightFirst && hits.length) move(1);
    }

    function close() {
      panel.hidden = true;
      active = -1;
      form.classList.remove('is-open');
      input.setAttribute('aria-expanded', 'false');
      input.removeAttribute('aria-activedescendant');
    }

    function move(d) {
      const opts = list.querySelectorAll('.xs-opt');
      if (!opts.length) return;
      active = (active + d + opts.length) % opts.length;
      opts.forEach((o, i) => o.setAttribute('aria-selected', i === active));
      input.setAttribute('aria-activedescendant', opts[active].id);
    }

    function submit(term) {
      const t = term.trim();
      status.textContent = t ? 'Showing results for “' + t + '”.' : 'Type a keyword to search the docs.';
      close();
    }

    function pick(opt) {
      input.value = opt.dataset.v;
      submit(opt.dataset.v);
    }

    form.querySelector('#xsBtn').addEventListener('click', e => {
      if (!form.classList.contains('is-open') && document.activeElement !== input) { e.preventDefault(); input.focus(); }
    });
    form.addEventListener('submit', () => {
      const o = list.querySelectorAll('.xs-opt')[active];
      if (o && !panel.hidden) pick(o); else submit(input.value);
    });
    input.addEventListener('focus', () => render());
    input.addEventListener('input', () => render());
    input.addEventListener('keydown', e => {
      if (e.key === 'ArrowDown') { e.preventDefault(); if (panel.hidden) render(); move(1); }
      else if (e.key === 'ArrowUp') { e.preventDefault(); move(-1); }
      else if (e.key === 'Escape') { input.value = ''; close(); input.blur(); }
    });
    list.addEventListener('mousedown', e => {
      const o = e.target.closest('.xs-opt');
      if (o) { e.preventDefault(); pick(o); }
    });
    document.addEventListener('pointerdown', e => { if (!form.contains(e.target)) close(); });
    form.addEventListener('focusout', () => setTimeout(() => { if (!form.contains(document.activeElement)) close(); }));
    document.addEventListener('keydown', e => {
      if (e.key === '/' && !/^(INPUT|TEXTAREA|SELECT)$/.test(document.activeElement.tagName)) { e.preventDefault(); input.focus(); }
    });

    render(true);
  }

  initExpandingSearch();
})();