diff --git a/internal/views/static/js/settings.js b/internal/views/static/js/settings.js
new file mode 100644
index 0000000..77c9f7a
--- /dev/null
+++ b/internal/views/static/js/settings.js
@@ -0,0 +1,266 @@
+var ALL_ENGINES = [
+  'wikipedia', 'arxiv', 'crossref', 'braveapi',
+  'qwant', 'duckduckgo', 'github', 'reddit', 'bing'
+];
+
+var DEFAULT_PREFS = {
+  theme: 'system',
+  engines: ALL_ENGINES.slice(),
+  safeSearch: 'moderate',
+  format: 'html'
+};
+
+var STORAGE_KEY = 'kafka_prefs';
+
+function loadPrefs() {
+  var stored = localStorage.getItem(STORAGE_KEY);
+  var prefs = DEFAULT_PREFS;
+  if (stored) {
+    try {
+      var parsed = JSON.parse(stored);
+      prefs = {
+        theme: parsed.theme || DEFAULT_PREFS.theme,
+        engines: parsed.engines || DEFAULT_PREFS.engines.slice(),
+        safeSearch: parsed.safeSearch || DEFAULT_PREFS.safeSearch,
+        format: parsed.format || DEFAULT_PREFS.format
+      };
+    } catch (e) {
+      prefs = DEFAULT_PREFS;
+    }
+  }
+  return prefs;
+}
+
+function savePrefs(prefs) {
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(prefs));
+}
+
+function applyTheme(theme) {
+  if (theme === 'system') {
+    document.documentElement.removeAttribute('data-theme');
+  } else {
+    document.documentElement.setAttribute('data-theme', theme);
+  }
+}
+
+function syncEngineInput(prefs) {
+  var input = document.getElementById('engines-input');
+  if (input) {
+    input.value = prefs.engines.join(',');
+  }
+}
+
+function closePanel() {
+  var popover = document.getElementById('settings-popover');
+  var trigger = document.getElementById('settings-trigger');
+  if (popover) {
+    popover.setAttribute('data-open', 'false');
+  }
+  if (trigger) {
+    trigger.setAttribute('aria-expanded', 'false');
+  }
+  if (trigger) {
+    trigger.focus();
+  }
+}
+
+function openPanel() {
+  var popover = document.getElementById('settings-popover');
+  var trigger = document.getElementById('settings-trigger');
+  if (popover) {
+    popover.setAttribute('data-open', 'true');
+  }
+  if (trigger) {
+    trigger.setAttribute('aria-expanded', 'true');
+  }
+  var firstFocusable = popover ? popover.querySelector('button, input, select, textarea, a[href], [tabindex]:not([tabindex="-1"])') : null;
+  if (firstFocusable) {
+    firstFocusable.focus();
+  }
+}
+
+function escapeHtml(str) {
+  return str
+    .replace(/&/g, '&')
+    .replace(/</g, '&lt;')
+    .replace(/>/g, '&gt;');
+}
+
+function renderPanel(prefs) {
+  var themeIcons = { light: '☀️', dark: '🌙', system: '⌨' };
+  var safeOptions = ['moderate', 'strict', 'off'];
+  var formatOptions = ['html', 'json', 'csv', 'rss'];
+
+  var html = '<div id="settings-panel-inner">';
+  html += '<h2>Settings</h2>';
+
+  // Theme buttons
+  html += '<fieldset><legend>Theme</legend>';
+  html += '<div class="theme-buttons">';
+  ['light', 'dark', 'system'].forEach(function(t) {
+    var checked = prefs.theme === t ? ' checked' : '';
+    var icon = escapeHtml(themeIcons[t]);
+    html += '<label><input type="radio" name="theme" value="' + escapeHtml(t) + '"' + checked + '> ' + icon + ' ' + escapeHtml(t.charAt(0).toUpperCase() + t.slice(1)) + '</label>';
+  });
+  html += '</div></fieldset>';
+
+  // Engine checkboxes
+  html += '<fieldset><legend>Engines</legend>';
+  html += '<div class="engine-grid">';
+  ALL_ENGINES.forEach(function(engine) {
+    var checked = prefs.engines.indexOf(engine) !== -1 ? ' checked' : '';
+    html += '<label><input type="checkbox" name="engine" value="' + escapeHtml(engine) + '"' + checked + '> ' + escapeHtml(engine) + '</label>';
+  });
+  html += '</div></fieldset>';
+
+  html += '<p class="notice">Engine changes apply to your next search.</p>';
+
+  // Safe search dropdown
+  html += '<label for="safe-search-select">Safe Search</label>';
+  html += '<select id="safe-search-select">';
+  safeOptions.forEach(function(opt) {
+    var selected = prefs.safeSearch === opt ? ' selected' : '';
+    html += '<option value="' + escapeHtml(opt) + '"' + selected + '>' + escapeHtml(opt.charAt(0).toUpperCase() + opt.slice(1)) + '</option>';
+  });
+  html += '</select>';
+
+  // Format dropdown
+  html += '<label for="format-select">Format</label>';
+  html += '<select id="format-select">';
+  formatOptions.forEach(function(opt) {
+    var selected = prefs.format === opt ? ' selected' : '';
+    html += '<option value="' + escapeHtml(opt) + '"' + selected + '>' + escapeHtml(opt.toUpperCase()) + '</option>';
+  });
+  html += '</select>';
+
+  html += '<button type="button" id="settings-close">Close</button>';
+  html += '</div>';
+
+  document.body.innerHTML = html;
+
+  // Attach listeners to theme buttons
+  var themeButtons = document.querySelectorAll('input[name="theme"]');
+  themeButtons.forEach(function(btn) {
+    btn.addEventListener('click', function() {
+      var newPrefs = loadPrefs();
+      newPrefs.theme = btn.value;
+      savePrefs(newPrefs);
+      applyTheme(newPrefs.theme);
+    });
+  });
+
+  // Attach listeners to engine checkboxes
+  var engineCheckboxes = document.querySelectorAll('input[name="engine"]');
+  engineCheckboxes.forEach(function(cb) {
+    cb.addEventListener('change', function() {
+      var newPrefs = loadPrefs();
+      if (cb.checked) {
+        if (newPrefs.engines.indexOf(cb.value) === -1) {
+          newPrefs.engines.push(cb.value);
+        }
+      } else {
+        newPrefs.engines = newPrefs.engines.filter(function(e) { return e !== cb.value; });
+      }
+      savePrefs(newPrefs);
+      syncEngineInput(newPrefs);
+    });
+  });
+
+  // Attach listener to safe search dropdown
+  var safeSelect = document.getElementById('safe-search-select');
+  if (safeSelect) {
+    safeSelect.addEventListener('change', function() {
+      var newPrefs = loadPrefs();
+      newPrefs.safeSearch = safeSelect.value;
+      savePrefs(newPrefs);
+    });
+  }
+
+  // Attach listener to format dropdown
+  var formatSelect = document.getElementById('format-select');
+  if (formatSelect) {
+    formatSelect.addEventListener('change', function() {
+      var newPrefs = loadPrefs();
+      newPrefs.format = formatSelect.value;
+      savePrefs(newPrefs);
+    });
+  }
+
+  // Attach listener to close button
+  var closeBtn = document.getElementById('settings-close');
+  if (closeBtn) {
+    closeBtn.addEventListener('click', closePanel);
+  }
+}
+
+function initSettings() {
+  var prefs = loadPrefs();
+  applyTheme(prefs.theme);
+  syncEngineInput(prefs);
+  renderPanel(prefs);
+
+  var trigger = document.getElementById('settings-trigger');
+  var triggerMobile = document.getElementById('settings-trigger-mobile');
+
+  function togglePanel() {
+    var popover = document.getElementById('settings-popover');
+    if (popover && popover.getAttribute('data-open') === 'true') {
+      closePanel();
+    } else {
+      openPanel();
+    }
+  }
+
+  if (trigger) {
+    trigger.addEventListener('click', togglePanel);
+  }
+  if (triggerMobile) {
+    triggerMobile.addEventListener('click', togglePanel);
+  }
+}
+
+// Escape key handler
+document.addEventListener('keydown', function(e) {
+  if (e.key === 'Escape') {
+    var popover = document.getElementById('settings-popover');
+    if (popover && popover.getAttribute('data-open') === 'true') {
+      closePanel();
+    }
+  }
+});
+
+// Click outside handler
+document.addEventListener('click', function(e) {
+  var popover = document.getElementById('settings-popover');
+  var trigger = document.getElementById('settings-trigger');
+  if (popover && popover.getAttribute('data-open') === 'true') {
+    if (!popover.contains(e.target) && (!trigger || !trigger.contains(e.target))) {
+      closePanel();
+    }
+  }
+});
+
+// Focus trap
+document.addEventListener('keydown', function(e) {
+  if (e.key === 'Tab') {
+    var popover = document.getElementById('settings-popover');
+    if (popover && popover.getAttribute('data-open') === 'true') {
+      var focusableElements = popover.querySelectorAll('button, input, select, textarea, a[href], [tabindex]:not([tabindex="-1"])');
+      var firstEl = focusableElements[0];
+      var lastEl = focusableElements[focusableElements.length - 1];
+      if (e.shiftKey && document.activeElement === firstEl) {
+        e.preventDefault();
+        lastEl.focus();
+      } else if (!e.shiftKey && document.activeElement === lastEl) {
+        e.preventDefault();
+        firstEl.focus();
+      }
+    }
+  }
+});
+
+if (document.readyState === 'loading') {
+  document.addEventListener('DOMContentLoaded', initSettings);
+} else {
+  initSettings();
+}