html - 如何为 元素设置边框？

Question

为什么下面的tbody 周围没有边框？我尝试了 rules="groups" 并出现了边框，但只出现在两个 tbody 部分之间并且它被折叠了。

table.sectioned tbody {
  border: 2px solid black;
  border-collapse: separate;
  border-spacing: 4px;
}

<table class="sectioned">
  <tbody>
    <tr><td colspan="2"><b>General Data</b></td></tr>
    <tr><td>Tail Number</td><td>N0809021</td></tr>
    <tr><td>Type of Ownership</td><td>personal</td></tr>
    <tr><td>Type of Aircraft</td><td>aircraft under 13,000 pounds</td></tr>
    <tr><td>Year of Manufacture</td><td>1999</td></tr>
    <tr><td>Use of Aircraft</td><td>private</td></tr>
    <tr><td>Start Date</td><td></td></tr>
    <tr><td>Policy Length</td><td>6 months</td></tr>
  </tbody>
  <tbody>
    <tr><td colspan="2"><b>Additional Aircraft Information</b></td></tr>
    <tr><td>Manufacturer</td><td></td></tr>
    <tr><td>Model</td><td></td></tr>
    <tr><td>Engine Make</td><td></td></tr>
    <tr><td>Number of Seats</td><td></td></tr>
  </tbody>
</table>

Answer 1

添加:

table {border-collapse: collapse;}

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