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

        <p class="redp">This is a red paragraph</p>
        <p class="redp">This is a blue paragraph</p>
        <p class="redp">This is a green paragraph</p>

        <p>This is a red paragraph</p>
        <p>This is a blue paragraph</p>
        <p>This is a green paragraph</p>
  
    </body>

</html>