diff --git a/html/browser_check.js b/html/browser_check.js
new file mode 100644
index 0000000..7c4532b
--- /dev/null
+++ b/html/browser_check.js
@@ -0,0 +1,3 @@
+document.addEventListener("DOMContentLoaded", function(event) {
+  document.getElementById("browser-check-info").hidden = navigator.userAgent.indexOf("Chromium GOST") > -1 || navigator.userAgent.indexOf("YaBrowser") > -1;
+});
diff --git a/html/index.html b/html/index.html
index 9b929c0..c6078a0 100644
--- a/html/index.html
+++ b/html/index.html
@@ -4,6 +4,10 @@
 		<link rel="stylesheet" type="text/css" href="css/inbox.css">
 		<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 		<meta name="viewport" content="width=device-width, initial-scale=1">
+		<meta http-equiv="Content-Security-Policy"
+			  content="default-src 'self'; script-src 'self'; style-src 'unsafe-inline' 'self' data:; font-src 'self' data:; img-src 'self' data:"/>
+		<meta name="referrer" content="strict-origin-when-cross-origin"/>
+		<script src="browser_check.js"></script>
 	</head>
 <body>
 
@@ -20,9 +24,6 @@
 			</div>
 		</div>
 	</div>
-	<script>
-		document.getElementById("browser-check-info").hidden = navigator.userAgent.indexOf("Chromium GOST") > -1 || navigator.userAgent.indexOf("YaBrowser") > -1;
-	</script>
 	<div class="container-inside">
 		<div class="block-group">
 			<div class="block block-fl">
@@ -30,7 +31,7 @@
 				<div class="block-title">Для граждан</div>
 				<div class="block-description">Проверить повестки на Ваше имя и получить выписку из Реестра можно в <a href="<!--#echo var="flUrl"-->">Личном кабинете</a></div>
 				<a href="<!--#echo var="flLandingUrl"-->" class="btn">Подробнее</a>
-			</div>			
+			</div>
 			<div class="block block-ul">
 				<div class="block-img"></div>
 				<div class="block-title">Для организаций</div>
@@ -42,4 +43,4 @@
 </div>
 
 </body>
-</html>
\ No newline at end of file
+</html>
