make table header sticky

Author: alok1304

docs/index.html

@@ -17,6 +17,7 @@
       .anchor {color: #6362dc; display: none; margin-left: .2rem; padding: 0 .2rem;}
       h4:focus .anchor, h4:hover .anchor {display: inline; text-decoration: none;}
       .help_text, .help_text:hover, .help_text:visited {color: #3b4351!important; border-bottom: dotted 0.0625rem #cccccc; text-decoration: inherit;}
+      .table-head{position: sticky; top: 0; overflow: hidden; background-color:  #FFFFFF;}
     </style>
     <link rel="stylesheet" href="static/spectre-0.5.9.min.css">
     <script src="static/jquery-3.5.1.slim.min.js"></script>
@@ -47,7 +48,7 @@
   <div class="container">
     <div class="loading loading-lg" style="margin-top:50px;"></div>
     <table class="display" style="visibility: hidden;">
-      <thead>
+      <thead class="table-head">
         <tr>
           <th>Key</th>
           <th>Short name</th>