diff --git a/rptools/rpviz/templates/css/viewer.css b/rptools/rpviz/templates/css/viewer.css
index 6d570a9..9523254 100644
--- a/rptools/rpviz/templates/css/viewer.css
+++ b/rptools/rpviz/templates/css/viewer.css
@@ -20,6 +20,37 @@ body {
     box-shadow: 0 0 5px 0px black;
 }
 
+/* Hide panels **************************************/
+#toggle-panels-container {
+    position: fixed;
+    top: 10px;
+    left: 50%;
+    transform: translateX(-50%);
+    z-index: 9999;
+}
+
+#toggle-panels {
+    padding: 6px 12px;
+    font-size: 13px;
+    cursor: pointer;
+}
+
+/* Hide panels */
+.panel-hidden {
+    display: none !important;
+}
+
+/* Expanded view when panels are hidden */
+#viewer.panels-hidden #cy {
+    width: 100%;
+    margin-left: 0;
+}
+
+#viewer.panels-hidden #interaction,
+#viewer.panels-hidden #info {
+    display: none !important;
+}
+
 /* Left panel: pathway level interaction **************************************/
 #interaction {
     position: absolute;
diff --git a/rptools/rpviz/templates/index.html b/rptools/rpviz/templates/index.html
index f3642d5..c8a8464 100644
--- a/rptools/rpviz/templates/index.html
+++ b/rptools/rpviz/templates/index.html
@@ -56,7 +56,55 @@
 <!--    <script src="js/cytoscape-cola-1.4.3.js"></script>-->
 
 </head>
+
+<!-- Controls for hiding panels -->
+<script>
+$(function () {
+
+    $('#toggle-panels').on('click', function () {
+    if (!window.cy) return;
+
+    const cyEl = document.getElementById('cy');
+
+    const oldPan = cy.pan();
+    const oldZoom = cy.zoom();
+    const oldLeft = cyEl.getBoundingClientRect().left;
+
+    $('#interaction, #info').toggleClass('panel-hidden');
+    $('#viewer').toggleClass('panels-hidden');
+
+    requestAnimationFrame(() => {
+        const newLeft = cyEl.getBoundingClientRect().left;
+
+        // Correct sign: compensate by how much the container shifted
+        const shift = oldLeft - newLeft;
+
+        cy.resize();
+        cy.zoom(oldZoom);
+        cy.pan({ x: oldPan.x + shift, y: oldPan.y });
+    });
+    });
+
+    function resizeCy() {
+    if (!window.cy) return;
+
+    // save current viewport
+    const z = cy.zoom();
+    const p = cy.pan();
+
+    cy.resize();          // let Cytoscape recompute its canvas size
+    cy.zoom(z);           // restore zoom
+    cy.pan(p);            // restore pan
+    // (no cy.fit())
+    }
+
+});
+</script>
+
 <body>
+    <div id="toggle-panels-container">
+        <button id="toggle-panels">Toggle panels</button>
+    </div>
 
     <div id="base">
 
