一.三角形
https://blog.csdn.net/Szu_AKer/article/details/51755821
notice:三角的那部分可以用图片作为背景,但是容易出现杂边。所以利用css中border做出三角形状,原理是用border的形状如下:
当我们设置content的宽高为0时,可想而知会出现什么效果,如下:
然后把不保留的其他boder设置颜色为透明transparent就行了。具体代码如下:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
.box{
position: relative;
padding-top: 8px;
}
.con{
width: 200px;
height: 100px;
border: 1px skyblue solid;
border-radius: 3px;
background-color: skyblue;
}
.con-ret{
border: 7px solid transparent;
border-bottom-color:skyblue;
position: absolute;
left: 10px;
top:-6px;
}
</style>
</head>
<body>
<div class="box">
<div class="con-ret"></div>
<div class="con"></div>
</div>
</body>
</html>
二. 箭头
1.右箭头
以下代码实现了两个向右的三角形
<body>
<span id="demo16">文字内容</span>
<style>
#demo16{
position: relative;
}
#demo16:after, #demo16:before {
border: 10px solid transparent;
border-left: 10px solid red;
width: 0;
height: 0;
position: absolute;
top: 0;
right: -20px;
content: ' '
} #demo16:before {
border-left-color: #fd0;
right: -31px;
}
</style>
</body>
将右边三角形左移,再把第一个三角形改为白色即可得到向右的箭头
<body>
<span id="demo16">文字内容</span>
<style>
#demo16{
position: relative;
}
#demo16:after, #demo16:before {
border: 10px solid transparent;
border-left: 10px solid #fff;
width: 0;
height: 0;
position: absolute;
top: 0;
right: -20px;
content: ' '
} #demo16:before {
border-left-color: red;
right: -21px;
}
</style>
</body>
下箭头
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>空心三角形指示箭头</title>
<style> /*第一个三角形*/
.all::before{ /*这里的伪元素用单冒号和双冒号都一样*/
content: '';
display: block;
position: absolute;
top: 14px;
left: 160px;
border-left: 8px solid transparent ;
border-right: 8px solid transparent;
border-top: 8px solid #555;
} /*第二个三角形*/
.all::after{
content: '';
display: block;
position: absolute;
top: 11.6px; /*向下偏移量是矩形边框宽度的1.4(根号2)倍,即8.4,top值为-26-(-8.4)*/
left: 160px;
border-left: 8px solid transparent;
border-right: 8px solid transparent;
border-top: 8px solid #ececec;
}
</style>
</head>
<body>
<a class="all"" href="#">全部商品分类</a>
</body>
</html>