diff --git a/templates/device_detail.html b/templates/device_detail.html
index c2293de..85069a7 100644
--- a/templates/device_detail.html
+++ b/templates/device_detail.html
@@ -210,12 +210,18 @@ function addInstallRow() {
     {% if ha_enabled %}
     <div class="form-group">
       <label for="edit-ha-entity">Home Assistant Entity ID</label>
-      <input type="text" id="edit-ha-entity" name="ha_entity_id"
-             value="{{ device.ha_entity_id or '' }}"
-             placeholder="e.g. sensor.tv_remote_battery"
-             list="ha-entities-list" autocomplete="off">
-      <datalist id="ha-entities-list"></datalist>
-      <small class="text-muted" id="ha-entities-status" style="display:block;margin-top:0.25rem;font-size:0.8rem;"></small>
+      <div style="position:relative;">
+        <input type="text" id="edit-ha-entity" name="ha_entity_id"
+               value="{{ device.ha_entity_id or '' }}"
+               placeholder="e.g. sensor.tv_remote_battery"
+               autocomplete="off">
+        <div id="ha-entity-dropdown"
+             style="display:none;position:absolute;left:0;right:0;top:100%;z-index:200;
+                    background:var(--bg-card);border:1px solid var(--border);border-radius:4px;
+                    max-height:220px;overflow-y:auto;box-shadow:0 4px 12px rgba(0,0,0,0.15);"></div>
+      </div>
+      <small class="text-muted" id="ha-entities-status"
+             style="display:block;margin-top:0.25rem;font-size:0.8rem;"></small>
     </div>
     {% endif %}
     <button class="btn btn-primary" type="submit">Save Changes</button>
@@ -237,24 +243,65 @@ function addInstallRow() {
 {% if ha_enabled %}
 <script>
 (function() {
-  var datalist = document.getElementById('ha-entities-list');
+  var input    = document.getElementById('edit-ha-entity');
+  var dropdown = document.getElementById('ha-entity-dropdown');
   var status   = document.getElementById('ha-entities-status');
-  if (!datalist) return;
+  if (!input || !dropdown) return;
 
-  function populate(entities) {
-    datalist.innerHTML = '';
-    entities.forEach(function(e) {
-      var opt = document.createElement('option');
-      opt.value = e.entity_id;
-      if (e.friendly_name && e.friendly_name !== e.entity_id) opt.label = e.friendly_name;
-      datalist.appendChild(opt);
+  var allEntities = [];
+
+  function renderDropdown(query) {
+    var q = query.toLowerCase();
+    var matches = q
+      ? allEntities.filter(function(e) {
+          return e.entity_id.toLowerCase().indexOf(q) !== -1
+              || (e.friendly_name && e.friendly_name.toLowerCase().indexOf(q) !== -1);
+        })
+      : allEntities;
+    if (!matches.length) { dropdown.style.display = 'none'; return; }
+    dropdown.innerHTML = '';
+    matches.slice(0, 60).forEach(function(e) {
+      var item = document.createElement('div');
+      item.style.cssText = 'padding:0.5rem 0.75rem;cursor:pointer;border-bottom:1px solid var(--border);';
+      var label = document.createElement('div');
+      label.style.cssText = 'font-size:0.875rem;word-break:break-all;';
+      label.textContent = e.entity_id;
+      item.appendChild(label);
+      if (e.friendly_name && e.friendly_name !== e.entity_id) {
+        var sub = document.createElement('div');
+        sub.style.cssText = 'font-size:0.75rem;color:var(--text-muted);';
+        sub.textContent = e.friendly_name;
+        item.appendChild(sub);
+      }
+      item.addEventListener('mousedown', function(ev) { ev.preventDefault(); });
+      item.addEventListener('click', function() {
+        input.value = e.entity_id;
+        dropdown.style.display = 'none';
+        input.focus();
+      });
+      item.addEventListener('mouseover', function() { this.style.background = 'var(--bg-hover)'; });
+      item.addEventListener('mouseout',  function() { this.style.background = ''; });
+      dropdown.appendChild(item);
     });
+    dropdown.style.display = 'block';
+  }
+
+  input.addEventListener('input',   function() { renderDropdown(this.value); });
+  input.addEventListener('focus',   function() { if (allEntities.length) renderDropdown(this.value); });
+  input.addEventListener('blur',    function() { setTimeout(function() { dropdown.style.display = 'none'; }, 150); });
+  input.addEventListener('keydown', function(e) { if (e.key === 'Escape') dropdown.style.display = 'none'; });
+  document.addEventListener('click', function(e) {
+    if (!input.contains(e.target) && !dropdown.contains(e.target)) dropdown.style.display = 'none';
+  });
+
+  function onEntities(entities) {
+    allEntities = entities;
     if (status) status.textContent = entities.length ? entities.length + ' battery entities available' : '';
   }
 
   try {
     var cached = sessionStorage.getItem('ha_battery_entities');
-    if (cached) { populate(JSON.parse(cached)); return; }
+    if (cached) { onEntities(JSON.parse(cached)); return; }
   } catch(e) {}
 
   if (status) status.textContent = 'Loading HA entities\u2026';
@@ -262,7 +309,7 @@ function addInstallRow() {
     .then(function(r) { return r.json(); })
     .then(function(entities) {
       try { sessionStorage.setItem('ha_battery_entities', JSON.stringify(entities)); } catch(e) {}
-      populate(entities);
+      onEntities(entities);
     })
     .catch(function() { if (status) status.textContent = ''; });
 }());