用css写出不同三角形

1、

#triangle-up {
    width: 0;
    height: 0;
    border-left: 50px solid transparent;
    border-right: 50px solid transparent;
    border-bottom: 100px solid black;
}

2、

#triangle-down {
    width: 0;
    height: 0;
    border-left: 50px solid transparent;
    border-right: 50px solid transparent;
    border-top: 100px solid black;
}

3、

#triangle-left {
    width: 0;
    height: 0;
    border-top: 50px solid transparent;
    border-bottom: 50px solid transparent;
    border-right: 100px solid black;
}

4、

#triangle-right {
    width: 0;
    height: 0;
    border-top: 50px solid transparent;
    border-bottom: 50px solid transparent;
    border-left: 100px solid black;
}

5、

#triangle-top-left {
    width: 0;
    height: 0;
    border-top: 100px solid black;
    border-right: 100px solid transparent;
}

6、

#triangle-top-right {
    width: 0;
    height: 0;
    border-top: 100px solid black;
    border-left: 100px solid transparent;
}

7、

#triangle-bottom-left {
    width: 0;
    height: 0;
    border-bottom: 100px solid black;
    border-right: 100px solid transparent;
}

8、

#triangle-bottom-right {
    width: 0;
    height: 0;
    border-bottom: 100px solid black;
    border-left: 100px solid transparent;
}