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Source: http://aduq-online.teachable.com/

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  5.    <title>404 Error - Teachable</title>
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  11.      body {
  12.        background: url('https://assets.teachablecdn.com/images/teachable-brand-bg.png')
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  14.        height: 100%;
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  30.        top: 50%;
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  37.        font-weight: 600 !important;
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  39.        background-color: #475b5c;
  40.        padding: 18px 22px 18px 22px;
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  44.      .article {
  45.        padding: 24px 18px 18px 18px;
  46.        font-size: 17px;
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  50.        color: #fff;
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  109.  </head>
  110.  <body>
  111.    <div class="section">
  112.      <div class="article">
  113.        <p class="large">This page does not exist. Sorry :(</p>
  114.        <p class="error-number">Error 404</p>
  115.      </div>
  116.    </div>
  117.    <h1 class="bottom">
  118.      <center>
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