diff --git a/lib/core/renderMarkdown.js b/lib/core/renderMarkdown.js
index 4828ad71a0a8..20775cc3f24c 100644
--- a/lib/core/renderMarkdown.js
+++ b/lib/core/renderMarkdown.js
@@ -24,7 +24,7 @@ class MarkdownRenderer {
     const md = new Markdown({
       // Highlight.js expects hljs css classes on the code element.
       // This results in <pre><code class="hljs css languages-jsx">
-      langPrefix: 'hljs css languages-',
+      langPrefix: 'hljs css language-',
       highlight(str, lang) {
         lang =
           lang || (siteConfig.highlight && siteConfig.highlight.defaultLang);
diff --git a/lib/static/css/prism.css b/lib/static/css/prism.css
index 3a997e04f3bd..74099294a523 100644
--- a/lib/static/css/prism.css
+++ b/lib/static/css/prism.css
@@ -1,14 +1,11 @@
 /**
- * prism.js default theme for JavaScript, CSS and HTML
+ * Modified prism.js default theme for JavaScript, CSS and HTML
  * Based on dabblet (http://dabblet.com)
  * @author Lea Verou
  */
 
 code[class*="language-"],
 pre[class*="language-"] {
-  color: black;
-  background: none;
-  text-shadow: 0 1px white;
   font-family: Consolas, Monaco, 'Andale Mono', 'Ubuntu Mono', monospace;
   text-align: left;
   white-space: pre;
@@ -27,23 +24,6 @@ pre[class*="language-"] {
   hyphens: none;
 }
 
-pre[class*="language-"]::-moz-selection, pre[class*="language-"] ::-moz-selection,
-code[class*="language-"]::-moz-selection, code[class*="language-"] ::-moz-selection {
-  text-shadow: none;
-}
-
-pre[class*="language-"]::selection, pre[class*="language-"] ::selection,
-code[class*="language-"]::selection, code[class*="language-"] ::selection {
-  text-shadow: none;
-}
-
-@media print {
-  code[class*="language-"],
-  pre[class*="language-"] {
-    text-shadow: none;
-  }
-}
-
 /* Code blocks */
 pre[class*="language-"] {
   padding: 1em;