三角形-css

/*箭头向上*/
.arrow-up {
    width:0; 
    height:0; 
    border-left:30px solid transparent;
    border-right:30px solid transparent;
    border-bottom:30px solid #000;
}
    
 /*箭头向下*/
.arrow-down {
    width:0; 
    height:0; 
    border-left:30px solid transparent;
    border-right:30px solid transparent;
    border-top:30px solid #0066cc;
}
    
 /*箭头向左*/
.arrow-left {
    width:0; 
    height:0; 
    border-top:30px solid transparent;
    border-bottom:30px solid transparent; 
    border-right:30px solid yellow; 
}
   
/*箭头向右*/
.arrow-right {
    width:0; 
    height:0; 
    border-top:30px solid transparent;
    border-bottom: 30px solid transparent;
    border-left: 30px solid green;
}

/*箭头无封口*/
.deg{
    width:30px;
    height:30px;
    border-left:1px solid red;
    border-bottom:1px solid red;
    margin-left:100px;
    transform:rotate(-45deg);
}