Dropdwn.HTML

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Drop Down Menu</title>
    <link rel="stylesheet" href="dropdown.css">
    <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.4.1/css/all.css" integrity="sha384-5sAR7xN1Nv6T6+dT2mhtzEpVJvfS3NScPQTrOxhwjIuvcA67KV2R5Jz6kr4abQsz" crossorigin="anonymous">
</head>
<body>
 <!-- Home work 4 -->
    <div style="margin-top:300px;">
        <ul class="triangle_menu">
            <li><a href="#">Menu Item</a></li>
            <li><a href="#">Menu Item</a>
                <ul class="sub_menu">
                    <li><a href="#">Sub Menu Item</a></li>
                    <li><a href="#">Sub Menu Item</a></li>
                    <li><a href="#">Sub Menu Item</a></li>
                </ul>
            </li>
            <li><a href="#">Menu Item</a></li>
            <li><a href="#">Menu Item</a></li>
        </ul>
    </div>
</body>