diff --git a/app/views/challenges/show.html.erb b/app/views/challenges/show.html.erb
index 92d1a2b01..913cede93 100644
--- a/app/views/challenges/show.html.erb
+++ b/app/views/challenges/show.html.erb
@@ -3,7 +3,7 @@
 
 <%= stylesheet_link_tag '/editormd/css/editormd','/editormd/css/editormd.min.css' %>
 <%= javascript_include_tag '/editormd/lib/marked.min.js','/editormd/lib/prettify.min.js','/editormd/lib/raphael.min.js','/editormd/lib/underscore.min.js','/editormd/lib/sequence-diagram.min.js',
-                        '/editormd/lib/flowchart.min.js','/editormd/lib/jquery.flowchart.min.js','/editormd/editormd.js'%>
+                        '/editormd/lib/flowchart.min.js','/editormd/lib/jquery.flowchart.min.js','/editormd/editormd.js' %>
 
 <style>
     .editormd-preview-container, .editormd-html-preview{
@@ -118,19 +118,21 @@
 </div>
 <script type="text/javascript">
     $(document).ready(function() {
-        var taskPassMD = editormd.markdownToHTML("challenge_task_pass", {
-            htmlDecode      : "style,script,iframe",  // you can filter tags decode
-            taskList        : true,
-            tex             : true,  // 默认不解析
-            flowChart       : true,  // 默认不解析
-            sequenceDiagram : true // 默认不解析
-        });
-        var answerMD = editormd.markdownToHTML("tpm_answer_show", {
-            htmlDecode      : "style,script,iframe",  // you can filter tags decode
-            taskList        : true,
-            tex             : true,  // 默认不解析
-            flowChart       : true,  // 默认不解析
-            sequenceDiagram : true // 默认不解析
+        editormd.loadKaTeX(function() {
+            var taskPassMD = editormd.markdownToHTML("challenge_task_pass", {
+                htmlDecode: "style,script,iframe",  // you can filter tags decode
+                taskList: true,
+                tex: true,  // 默认不解析
+                flowChart: true,  // 默认不解析
+                sequenceDiagram: true // 默认不解析
+            });
+            var answerMD = editormd.markdownToHTML("tpm_answer_show", {
+                htmlDecode: "style,script,iframe",  // you can filter tags decode
+                taskList: true,
+                tex: true,  // 默认不解析
+                flowChart: true,  // 默认不解析
+                sequenceDiagram: true // 默认不解析
+            });
         });
     });
 </script>
diff --git a/public/editormd/editormd.js b/public/editormd/editormd.js
index d9c3443a2..42bd32616 100644
--- a/public/editormd/editormd.js
+++ b/public/editormd/editormd.js
@@ -4014,7 +4014,7 @@
             var katexHandle = function() {
                 div.find("." + editormd.classNames.tex).each(function(){
                     var tex  = $(this);                    
-                    katex.render(tex.html().replace(/&lt;/g, "<").replace(/&gt;/g, ">"), tex[0]);                    
+                    katex.render(tex.text(), tex[0]);
                     tex.find(".katex").css("font-size", "1.0em");
                 });
             };
@@ -4178,8 +4178,8 @@
     // 使用国外的CDN，加载速度有时会很慢，或者自定义URL
     // You can custom KaTeX load url.
     editormd.katexURL  = {
-        css : "//cdnjs.cloudflare.com/ajax/libs/KaTeX/0.3.0/katex.min",
-        js  : "//cdnjs.cloudflare.com/ajax/libs/KaTeX/0.3.0/katex.min"
+        css : "/katex/katex.min",
+        js  : "/katex/katex.min"
     };
     
     editormd.kaTeXLoaded = false;
diff --git a/public/images/inner/saoma-qq.jpg b/public/images/inner/saoma-qq.jpg
index d23fe6a40..edf52858f 100644
Binary files a/public/images/inner/saoma-qq.jpg and b/public/images/inner/saoma-qq.jpg differ