diff --git a/_includes/footer.html b/_includes/footer.html
index 068cfb6..8554ea9 100644
--- a/_includes/footer.html
+++ b/_includes/footer.html
@@ -7,8 +7,10 @@
 <script async src="https://www.googletagmanager.com/gtag/js?id=G-0SJWMV04JW"></script>
 <script>
   window.dataLayer = window.dataLayer || [];
-  function gtag(){dataLayer.push(arguments);}
-  gtag('js', new Date());
+  function gtag() {
+    dataLayer.push(arguments);
+  }
+  gtag("js", new Date());
 
-  gtag('config', 'G-0SJWMV04JW');
+  gtag("config", "G-0SJWMV04JW");
 </script>
diff --git a/_includes/head.html b/_includes/head.html
index 996c85e..adf2dfa 100644
--- a/_includes/head.html
+++ b/_includes/head.html
@@ -1,25 +1,22 @@
 <head>
-  <meta http-equiv="content-type" content="text/html; charset=utf-8">
+  <meta http-equiv="content-type" content="text/html; charset=utf-8" />
 
   <!-- Enable responsiveness on mobile devices-->
-  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1">
-  <meta name="description" content="{{ site.title }}">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1" />
+  <meta name="description" content="{{ site.title }}" />
 
-  <link rel="apple-touch-icon" sizes="180x180" href="{{ site.baseurl }}/apple-touch-icon.png">
-  <link rel="icon" type="image/png" sizes="32x32" href="{{ site.baseurl }}/favicon-32x32.png">
-  <link rel="icon" type="image/png" sizes="16x16" href="{{ site.baseurl }}/favicon-16x16.png">
-  <link rel="shortcut icon" href="{{ site.baseurl }}/favicon.ico">
+  <link rel="apple-touch-icon" sizes="180x180" href="{{ site.baseurl }}/apple-touch-icon.png" />
+  <link rel="icon" type="image/png" sizes="32x32" href="{{ site.baseurl }}/favicon-32x32.png" />
+  <link rel="icon" type="image/png" sizes="16x16" href="{{ site.baseurl }}/favicon-16x16.png" />
+  <link rel="shortcut icon" href="{{ site.baseurl }}/favicon.ico" />
 
   <title>
-    {% if page.title == "Home" %}
-      {{ site.title }} &middot; {{ site.tagline }}
-    {% else %}
-      {{ page.title }} &middot; {{ site.title }}
-    {% endif %}
+    {% if page.title == "Home" %} {{ site.title }} &middot; {{ site.tagline }} {% else %} {{ page.title }} &middot; {{
+    site.title }} {% endif %}
   </title>
 
   <!-- CSS -->
-  <link rel="stylesheet" href="{{ site.baseurl }}/css/simple.min.css">
-  <link rel="stylesheet" href="{{ site.baseurl }}/css/highlight.css">
-  <link rel="stylesheet" href="{{ site.baseurl }}/css/custom.css?bust={{ site.time | date: '%s' }}">
+  <link rel="stylesheet" href="{{ site.baseurl }}/css/simple.min.css" />
+  <link rel="stylesheet" href="{{ site.baseurl }}/css/highlight.css" />
+  <link rel="stylesheet" href="{{ site.baseurl }}/css/custom.css?bust={{ site.time | date: '%s' }}" />
 </head>
diff --git a/_includes/languages.html b/_includes/languages.html
index 7268d23..e911c41 100644
--- a/_includes/languages.html
+++ b/_includes/languages.html
@@ -1,5 +1,5 @@
 <select id="languages">
   {% for language in site.data.languages %}
-    <option value="{{language.id}}">{{language.name}}</option>
+  <option value="{{language.id}}">{{language.name}}</option>
   {% endfor %}
-</select>
\ No newline at end of file
+</select>
diff --git a/_layouts/default.html b/_layouts/default.html
index b60a4ed..cbe3cc9 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -1,6 +1,5 @@
-<!DOCTYPE html>
+<!doctype html>
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en-us">
-
   {% include head.html %}
 
   <body>
diff --git a/_layouts/javascript.html b/_layouts/javascript.html
index 09dde33..0daf94f 100644
--- a/_layouts/javascript.html
+++ b/_layouts/javascript.html
@@ -1,10 +1,8 @@
-<!DOCTYPE html>
+<!doctype html>
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en-us">
-
   {% include head.html %}
 
   <body>
-
     {% include javascript_header.html %}
 
     <main>
diff --git a/_layouts/ruby.html b/_layouts/ruby.html
index a82ae3d..7160ebb 100644
--- a/_layouts/ruby.html
+++ b/_layouts/ruby.html
@@ -1,10 +1,8 @@
-<!DOCTYPE html>
+<!doctype html>
 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en-us">
-
   {% include head.html %}
 
   <body>
-
     {% include ruby_header.html %}
 
     <main>
diff --git a/index.html b/index.html
index 37c26c3..3096737 100644
--- a/index.html
+++ b/index.html
@@ -3,7 +3,10 @@
 title: Write snippet code to rewrite your source code
 ---
 
-<p>Different than other linter tools (e.g. rubocop) or codemod tools (e.g. jscodeshift), synvert allows you to write snippet code to rewrite your source code.</p>
+<p>
+  Different than other linter tools (e.g. rubocop) or codemod tools (e.g. jscodeshift), synvert allows you to write
+  snippet code to rewrite your source code.
+</p>
 
 <ul>
   <li>It is a complete solution to automatically rewrite (refactor) your source code.</li>
@@ -16,7 +19,9 @@
 <div class="downloads">
   <a id="mac-download" href="#"><button>Download Mac App</button></a>
   <a id="win-download" href="#"><button>Download Windows App</button></a>
-  <a href="https://marketplace.visualstudio.com/items?itemName=xinminlabs.synvert" target="_blank"><button>Install VSCode Extension</button></a>
+  <a href="https://marketplace.visualstudio.com/items?itemName=xinminlabs.synvert" target="_blank"
+    ><button>Install VSCode Extension</button></a
+  >
   <a href="/ruby/docs/"><button>Install Ruby CLI</button></a>
   <a href="/javascript/docs/"><button>Install Javascript CLI</button></a>
 </div>
@@ -26,9 +31,9 @@
     <div class="text">
       <h4>Run snippet code</h4>
       <p>
-        Synvert rewrites source code based on snippet code.<br/>
-        It provides many powerful APIs to write snippet code,<br/>
-        to find AST node, to check node <br/>
+        Synvert rewrites source code based on snippet code.<br />
+        It provides many powerful APIs to write snippet code,<br />
+        to find AST node, to check node <br />
         and to insert / delete / replace source code.
       </p>
     </div>
@@ -39,8 +44,8 @@ <h4>Run snippet code</h4>
     <div class="text">
       <h4>Automatically generate snippet code</h4>
       <p>
-        Synvert allows you to fill in some input code and expected output code,<br/>
-        then it can generate the snippet code automatically for you,<br/>
+        Synvert allows you to fill in some input code and expected output code,<br />
+        then it can generate the snippet code automatically for you,<br />
         usually you can use the generated code to rewrite your source code.
       </p>
     </div>
@@ -49,8 +54,8 @@ <h4>Automatically generate snippet code</h4>
     <div class="text">
       <h4>Show diff view</h4>
       <p>
-        Synvert GUI can show the diff view before rewriting,<br/>
-        so you can review the changes one by one,<br/>
+        Synvert GUI can show the diff view before rewriting,<br />
+        so you can review the changes one by one,<br />
         then selectivly replace them.
       </p>
     </div>
