代码块通常采用四个空格或一个制表符缩进。当它们被放在列表中时，请将它们缩进八个空格或两个制表符。
```
1. Open the file.
2. Find the following code block on line 21:
<html>
<head>
<title>Test</title>
</head>
3. Update the title to match the name of your website.
```
渲染效果如下：
1. Open the file.
2. Find the following code block on line 21:
```
<html>
<head>
<title>Test</title>
</head>
```
3. Update the title to match the name of your website.