How can I draw a left pointing triangle using CSS?

问题

It has been a long time since I built this triangle which points up. How can I alter my CSS to point the corner left?

http://jsfiddle.net/3sP8q/

.left-corner {
    width: 0;
    height: 0;
    border-bottom: 15px solid #000;
    border-left: 15px solid transparent;
    border-right: 15px solid transparent;
    position: relative;
}

<div class="left-corner"></div>

回答1:

Here is how:

.left-corner {
    width: 0;
    height: 0;
    border-top: 50px solid transparent;
    border-right: 100px solid red;
    border-bottom: 50px solid transparent;
}

<div class="left-corner"></div>

Use CSS-Tricks, it helps a lot!

来源：https://stackoverflow.com/questions/20076388/how-can-i-draw-a-left-pointing-triangle-using-css