在CSS3中制作小三角形效果代码

/*箭头向上*/
.arrow-up {
width:0;
height:0;
border-left:30px solid transparent;
border-right:30px solid transparent;
border-bottom:30px solid #f00;
}

/*箭头向右*/
.arrow-right {
width:0;
height:0;
border-top:20px solid transparent;
border-bottom: 20px solid transparent;
border-left: 20px solid green;
}

/*箭头向下*/
.arrow-down {
width:0;
height:0;
border-left:40px solid transparent;
border-right:40px solid transparent;
border-top:40px solid #ccc;
}

/*箭头向左*/
.arrow-left {
width:0;
height:0;
border-top:30px solid transparent;
border-bottom:30px solid transparent;
border-right:30px solid #00f;
}