CSS實現三角效果

<i class="triangle"></i>

.triangle {
     transform: rotate(45deg);
     display: block;
     width: 12px;
     height: 12px;
     border: 1px solid #9e9e9e;
     border-top-color: transparent;
     border-right-color: transparent;
     background-color: #fff;
}

<i class="triangle"></i>

.triangle {
     display: block;
     position: absolute;
     width: 0;
     border-width: 6px;
     border-color: transparent transparent red;
     border-style: dashed dashed solid;
     top: -12px;
     right: 76px;
}