代码编辑器：
x
1
2
<meta charset="utf-8">3
<link href="/static/next/css/tryit.css?v=2017082407" rel="stylesheet"/> 4
<style>5
table, th, td {6
border: 1px solid black;7
}8
tr.collapse {9
visibility: collapse;10
}11
</style>12
<table>13
<tr>14
<th>Firstname</th>15
<th>Lastname</th>16
</tr>17
<tr>18
<td>Peter</td>