一目了然的css边框三角形
css实现边框三角形的方法:
<div class="triangle up"></div>
<div class="triangle right"></div>
<div class="triangle down"></div>
<div class="triangle left"></div>
.triangle {
width: 0;
height: 0;
border-style: solid;
}
/* up */
.up {
border-width: 0 10px 10px;
border-color: transparent transparent #f00;
}
/* right */
.right {
border-width: 20px 0 20px 20px;
border-color: transparent transparent transparent #f00;
}
/* down */
.down {
border-width: 30px 30px 0;
border-color: #f00 transparent transparent;
}
/* left */
.left {
border-width: 40px 40px 40px 0;
border-color: transparent #f00 transparent transparent;
}
或这种写法:
.triangle {
width: 0;
height: 0;
border-style: solid;
}
/* up */
.up {
border-width: 10px;
border-top-width: 0;
border-color: transparent;
border-bottom-color: #f00;
}
/* right */
.right {
border-width: 20px;
border-right-width: 0;
border-color: transparent;
border-left-color: #f00;
}
/* down */
.down {
border-width: 30px;
border-bottom-width: 0;
border-color: transparent;
border-top-color: #f00;
}
/* left */
.left {
border-width: 40px;
border-left-width: 0;
border-color: transparent;
border-right-color: #f00;
}
以上代码效果如下:
总结:
1、元素的display: block | inline-block;
2、元素width,height为0;
3、向上三角形的border-top-width:0; border-bottom-color: #f00; 即向上方向时,上边宽长度为0,与之相反的下边框颜色不透明即可。其他方向依次类推(一句话总结即:同方向边的边框宽度为零其他三边有宽度,对立方向的颜色不为透明其它三边透明)