console 命令行工具 X clear
console
<!DOCTYPE html>
<!-- File: CSS_selectors002.html -->
<html>
    <head>
        <style>
            #redp {
                color: red;
            }
            #bluep {
                color: blue;
            }
            #greenp {
                color: green;
            }
        </style>
    </head>
    <body>

        <p id="redp">This is a red paragraph</p>
        <p id="bluep">This is a blue paragraph</p>
        <p id="greenp">This is a green paragraph</p>
  
    </body>

</html>