fix sum overlay and optimze for mobile

styles.css

@@ -119,6 +119,20 @@ body {
     pointer-events: none;
 }
 
+.sum-display {
+    position: absolute;
+    top: 10px;
+    left: 10px;
+    background: rgba(0, 0, 0, 0.8);
+    color: white;
+    padding: 10px 15px;
+    border-radius: 4px;
+    font-size: 14px;
+    z-index: 1000;
+    pointer-events: none;
+    display: none;
+}
+
 #nodeCount {
     font-size: 12px;
 }
@@ -159,3 +173,71 @@ body {
 .node-marker {
     z-index: 1000 !important;
 }
+
+/* Sidebar toggle button */
+.sidebar-toggle {
+    display: none;
+    position: fixed;
+    top: 15px;
+    left: 15px;
+    z-index: 2000;
+    background: #2c3e50;
+    color: white;
+    border: none;
+    padding: 12px;
+    font-size: 18px;
+    border-radius: 5px;
+    cursor: pointer;
+    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
+}
+
+.sidebar-toggle:hover {
+    background: #34495e;
+}
+
+/* Mobile styles */
+@media (max-width: 768px) {
+    .sidebar-toggle {
+        display: block;
+    }
+    
+    .toolbar {
+        position: fixed;
+        left: -250px;
+        top: 0;
+        height: 100vh;
+        transition: left 0.3s ease;
+        z-index: 1500;
+        box-shadow: 2px 0 10px rgba(0,0,0,0.3);
+    }
+    
+    .toolbar.open {
+        left: 0;
+    }
+    
+    .map-container {
+        width: 100%;
+    }
+    
+    /* Adjust sum display position on mobile to avoid toggle button */
+    .sum-display {
+        top: 70px;
+        left: 10px;
+    }
+    
+    /* Overlay when sidebar is open */
+    .sidebar-overlay {
+        display: none;
+        position: fixed;
+        top: 0;
+        left: 0;
+        width: 100%;
+        height: 100%;
+        background: rgba(0,0,0,0.5);
+        z-index: 1400;
+    }
+    
+    .sidebar-overlay.show {
+        display: block;
+    }
+}