1. The small triangle is achieved by setting a large enough border for a div and setting its top border, right border, left border, and background color to transparent, as follows:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
#demo {
width: 0;
height: 0;
/*边框的宽20px*/
border-width: 20px;
/*边框样式,实线*/
border-style: solid;
/*边框颜色*/
border-color: transparent transparent red transparent;
}
</style>
</head>
<body>
<!--小三角，transparent透明的，-->
<div id="demo">
</div>
</body>
</html>2. Problems with the mobile version of the a tag:
1》When you click the a tag, it will have a default background color. Solution
1 -webkit-tap-highlight-color:transparent;
2》Underline may appear when clicked, solution1 text-decoration: none; //或者2 3 border: none；//或者4 5 outline:none;
a:hover{
text-decoration:none;
}The above is the detailed content of Example tutorial on setting the background color to transparent. For more information, please follow other related articles on the PHP Chinese website!
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
