visual tweaks

previewers/betatest/ROCrateDeltablot.html

@@ -11,11 +11,10 @@
     <script src="lib/jquery.i18n.language.js"></script>
     <script type="text/javascript" src="js/retriever.js"></script>
     <!-- Latest compiled and minified CSS -->
-    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css"
-        integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">
+    <link rel='stylesheet' type='text/css'
+        href='https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css'/>
     <!-- Optional theme -->
-    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap-theme.min.css"
-        integrity="sha384-6pzBo3FDv/PJ8r2KRkGHifhEocL+1X2rVCTTkUfGk7/0pbek5mMa1upzvWbrUbOZ" crossorigin="anonymous">
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap-theme.min.css"/>
     <link type="text/css" rel="stylesheet" href="css/preview.css" />
 </head>
 
@@ -36,13 +35,13 @@ <h1 class="page-title rocratePreviewText">RO-Crate Preview</h1>
                         --main-bg: #f4f6f7;
                         --border: #cdcdcd;
                     }
-
+            
                     body {
                         background-color: var(--main-bg);
                         padding-left: 2vw;
                         color: #444;
                     }
-
+            
                     .ro-crate2htmlKey {
                         font-weight: bold;
                         margin-right: 1em;