child.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>Document</title>
    <style>
    ol>li{
        color:red;
    }
    </style>
</head>
<body>
    <ol>
        <li>list item one</li>
        <li>list item two</li>
        <ul>
            <li>sublist item one</li>
            <li>sublist item two</li>
        </ul>
        <li>list item three</li>
    </ol>

    <ul>
        <li>another item list</li>
    </ul>

</body>
</html>