CSS表格怎么让内边框变粗啊!!

img

像这样的表格周围是粗的,内部是细的
我尝试过在style那里用 table th td tr{},不行啊
帮帮我这个大学生!!


<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        table,td,th {
            border: 2px solid #000;
        }
    </style>
</head>
<body>
    <div>
        <table cellspacing="0" cellpadding="0">
            <tr>
                <th>id</th>
                <th>姓名</th>
            </tr>
            <tr>
                <td>1</td>
                <td>张三</td>
            </tr>
            <tr>
                <td>2</td>
                <td>李四</td>
            </tr>
        </table>
    </div>
</body>
</html>

表格的 boder?变粗 给table加 border

  table{
         border: 2px solid red;
      }

你说的是内边距嘛