<article id="article">
  <h1>내정보</h1>
  <div class="content">
    <p>내정보다</p>
    <table class="info">
      <thead>
        <tr>
          <th>이름</th>
          <th>나이</th>
          <th>직업</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td>진우</td>
          <td>27</td>
          <td>
            <section id="job">
              <table class="info">
                <tbody>
                  <tr>
                    <th>하는일</th>
                    <td>front-end web dev.</td>
                  </tr>
                </tbody>
              </table>
            </section> 
          </td>
        </tr>
      </tbody>
    </table>
  </div>
</article>

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  width: 300px;
}
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  margin: 0;
  padding: 0 1em;
  background: #ccc;
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#article .content {
  margin: 0;
  padding: 2em;
  background-color: #efefef;
}
#article .info th,
#article .info td {
  padding: 1em;
  border: 2px dashed #00f;   
}

#article .info th {
  color: #fff;
  background-color: #0aa;
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#job .info th,
#job .info td {
  padding: .5em;
  border-width: 1px;
  border-style: solid;
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