Simple issue HTML/CSS not working : <p>The stylesheet is linked correctly. I have not done HTML/CSS in ages, however, this seems straight forward. What is not correct?</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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<pre class="snippet-code-css lang-css prettyprint-override"><code>.box{
width:100px;
height:100px;
}

.box #1{
border: 1px solid red;
}

.box #2{
border: 1px solid blue;
}</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
  &lt;link rel="stylesheet" type="text/css" href="style.css"&gt;
&lt;/head&gt;
&lt;body&gt;
The content of the document......
&lt;div class = "box" id = "1"&gt;&lt;/div&gt;
&lt;div class = "box" id = "2"&gt;&lt;/div&gt;
&lt;/body&gt;
 
&lt;/html&gt;</code></pre>
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</div>
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