<html>
<head>
    <style>
        #grad {
            height: 50px;
            width: 50px;
            background: conic-gradient(at -10px -10px, blue 0deg, blue 90deg, orange 90deg, orange 180deg, green 180deg, green 270deg, blue 270deg, blue 360deg);
        }
    </style>
</head>
<body>
    <div id="grad"></div>
</body>
</html>