diff --git a/assets/index.html b/assets/index.html
index 264c7a1..c0b3423 100644
--- a/assets/index.html
+++ b/assets/index.html
@@ -7,7 +7,8 @@
     <script type='text/javascript' src="lws-common.js"></script>
  <title>Sai</title>
  </head>
-	<body>
+	<body class="overlay-active">
+		<div class="overlay"></div>
 		<div class="summary nailed">
 		<table><tr><td class="topregion">
 			<div class="logo">
diff --git a/assets/sai.css b/assets/sai.css
index 91f3c4c..f825a86 100644
--- a/assets/sai.css
+++ b/assets/sai.css
@@ -974,3 +974,17 @@ img.branch {
 .step-bar-completed {
     background-color: black;
 }
+
+.overlay {
+    position: fixed;
+    width: 100%;
+    height: 100%;
+    top: 0;
+    left: 0;
+    background-color: rgba(0, 0, 0, 0.5);
+    z-index: 2000;
+}
+
+body.overlay-active {
+    overflow: hidden;
+}
diff --git a/assets/sai.js b/assets/sai.js
index 0bc7372..9eec0d8 100644
--- a/assets/sai.js
+++ b/assets/sai.js
@@ -1122,6 +1122,12 @@ function ws_open_sai()
 
 	try {
 		sai.onopen = function() {
+			var overlay = document.querySelector(".overlay");
+			if (overlay) {
+				overlay.parentNode.removeChild(overlay);
+			}
+			document.body.classList.remove("overlay-active");
+
 			var par = new URLSearchParams(window.location.search),
 				tid, eid;
 			tid = par.get('task');
@@ -1755,6 +1761,11 @@ function ws_open_sai()
 		};
 
 		sai.onclose = function(ev){
+			var overlay = document.createElement("div");
+			overlay.className = "overlay";
+			document.body.appendChild(overlay);
+			document.body.classList.add("overlay-active");
+
 			console.log("WebSocket closed. Code:", ev.code, "Reason:", ev.reason);
 			myVar = setTimeout(ws_open_sai, 4000);
 		};