Replace form with div to avoid default button handling

main/index.html

@@ -140,7 +140,7 @@
         </div>
 
         <div class="card">
-            <form id="configForm" class="controls">
+            <div class="controls">
                 <div>
                     <label>Sample Rate (Hz)</label>
                     <input type="number" id="sampleRate" value="10000" min="1" max="83333">
@@ -171,9 +171,9 @@
                 </div>
                 <div>
                     <button id="resetBtn">Reset</button>
-                    <button id="powerOff"><a style="text-decoration: none; color: inherit" href="/poweroff">Power off</a></button>
+                    <button id="powerOff">Power off</button>
                 </div>
-            </form>
+            </div>
         </div>
 
         <div id="deltaPanel"></div>

main/index.js

@@ -150,8 +150,6 @@ canvas.addEventListener('click', (event) => {
       voltage,
       time: timeOffset
     };
-
-    // draw(); // Removed: Animation loop handles this
   }
 });
 
@@ -411,21 +409,19 @@ function setParams() {
     method: 'POST',
     headers: { 'Content-Type': 'application/json' },
     body: JSON.stringify(payload)
-  })
+  }).then(res => {
-    .then(res => {
+    if (res.ok) {
-      if (res.ok) {
+      resetLowRateState();
-        resetLowRateState();
 
-        // Update active config
+      // Update active config
-        activeConfig = { ...payload, desiredRate, trigger: parseInt(triggerLevel.value) || 2048 };
+      activeConfig = { ...payload, desiredRate, trigger: parseInt(triggerLevel.value) || 2048 };
 
-        // Save to localStorage
+      // Save to localStorage
-        localStorage.setItem('esp32_adc_config', JSON.stringify(activeConfig));
+      localStorage.setItem('esp32_adc_config', JSON.stringify(activeConfig));
-      } else {
+    } else {
-        alert('Error updating configuration');
+      alert('Error updating configuration');
-      }
+    }
-    })
+  }).catch(err => alert('Network error: ' + err));
-    .catch(err => alert('Network error: ' + err));
 };
 
 // Load config from localStorage on startup
@@ -452,6 +448,6 @@ document.getElementById('resetBtn').addEventListener('click', () => {
   localStorage.clear();
   window.location.reload();
 });
+document.getElementById('powerOff').addEventListener('click', () => window.location.href = "/poweroff");
 setParams();
 connect();
-