为什么写出来的颜色不显示？
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>borderyu 三角形</title>
<style type="text/css">
.triangle{width: 100px;height: 200px;
border:100px solid;
border-color: red green red yellow；
}
</style>
</head>
<body>
<div class="triangle">三角形</div>
</body>
</html>
