diff --git a/js/h5p.js b/js/h5p.js
index a55a87c..504d8d0 100644
--- a/js/h5p.js
+++ b/js/h5p.js
@@ -539,7 +539,13 @@ H5P.fullScreen = function ($element, instance, exitCallback, body) {
 
     before('h5p-semi-fullscreen');
     var $disable = H5P.jQuery('<div role="button" tabindex="1" class="h5p-disable-fullscreen" title="' + H5P.t('disableFullscreen') + '"></div>').appendTo($container.find('.h5p-content-controls'));
-    var keyup, disableSemiFullscreen = function () {
+    var keyup, disableSemiFullscreen = H5P.exitFullScreen = function () {
+      if (lastViewport) {
+        metaTags[i].content = lastViewport;
+      }
+      else {
+        head.removeChild(metaTag);
+      }
       $disable.remove();
       $body.unbind('keyup', keyup);
       done('h5p-semi-fullscreen');
@@ -551,6 +557,27 @@ H5P.fullScreen = function ($element, instance, exitCallback, body) {
     };
     $disable.click(disableSemiFullscreen);
     $body.keyup(keyup);
+
+    // Disable zoom
+    var lastViewport;
+    var metaTags = document.getElementsByTagName('meta');
+    for (var i = 0; i < metaTags.length; i++) {
+      if (metaTags[i].name === 'viewport') {
+        lastViewport = metaTags[i].content;
+        break;
+      }
+    }
+    if (!lastViewport) {
+      // Create tag
+      metaTags[i] = document.createElement('meta');
+      metaTags[i].name = 'viewport';
+    }
+    metaTags[i].content = 'width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0';
+    if (!lastViewport) {
+      var head = document.getElementsByTagName('head')[0];
+      head.appendChild(metaTag);
+    }
+
     entered();
   }
   else {
diff --git a/styles/h5p.css b/styles/h5p.css
index 3fca24e..4586952 100644
--- a/styles/h5p.css
+++ b/styles/h5p.css
@@ -130,13 +130,15 @@ div.h5p-fullscreen {
 }
 
 .h5p-iframe-wrapper.h5p-semi-fullscreen {
-  width: 100%;
-  height: 100%;
+  width: auto;
+  height: auto;
   background: black;
   position: fixed;
   top: 0;
   left: 0;
-  z-index: 1000;
+  right: 0;
+  bottom: 0;
+  z-index: 100001;
 }
 .h5p-iframe-wrapper.h5p-semi-fullscreen .buttons {
   position: absolute;