语法高亮，滚动条美化，设置页面调整

docs/javascript/Reference/Functions/arguments/length.html

@@ -2,20 +2,20 @@
 <div></div>
 <p>本次函数调用时传入函数的实参数量.</p>
 <h2 id="Syntax">Syntax</h2>
-<pre class="syntaxbox">arguments.length</pre>
+<pre><code class="language-javascript">arguments.length</code></pre>
 <h2 id="Description" name="Description">描述</h2>
 <p>arguments.length表示的是实际上向函数传入了多少个参数,这个数字可以比形参数量大,也可以比形参数量小(形参数量的值可以通过<a href="/zh-CN/docs/JavaScript/Reference/Global_Objects/Function/length" title="JavaScript/Reference/Global Objects/Function/length">Function.length</a>获取到).</p>
 <h2 id="Examples" name="Examples">例子</h2>
 <h3 id="Example:_Using_arguments.length" name="Example:_Using_arguments.length">例子: 使用<code>arguments.length</code></h3>
 <p>这个例中,我们定义了一个可以相加任意个数字的函数.</p>
-<pre class="brush: js">function adder(base, /*, n2, ... */) {
+<pre><code  class="language-javascript">function adder(base, /*, n2, ... */) {
   base = Number(base);
   for (var i = 0; i &lt; arguments.length; i++) {
     base += Number(arguments[i]);
   }
   return base;
 }
-</pre>
+</code></pre>
 <h2 id="Specifications">Specifications</h2>
 <table class="standard-table">
 <tbody>