纯css实现实心三角形

当一个div设置宽高为0，border宽度为50px时的效果是这样的

#triangle-up {
    width:0px;
    height:0px;
    border-width:50px;
    border-style:solid;
    border-color:#e66161 #f3bb5b #94e24f #85bfda;
}

那么如果只设置left top bottom的话呢……

#triangle-up {
    width:0px;
    height:0px;
    border-top: 50px solid transparent;
    border-left: 50px solid #f3bb5b;
    border-bottom: 50px solid transparent;
}

so...