<!DOCTYPE html>
<html lang="en">
    <head>
        <title>CSS</title>
        <meta charset="utf-8">
        <style>
.div1 { 
    width: 200px;
    height: 200px;
    background-color: #D1ECFF;
    border: 3px dashed #000000;
    padding: 5px; 
}

.div2 { 
    width: 100px;
    height: 100px;
    background-color: #ffffff;
    border: 3px ridge #000000;
    padding: 5px;
    margin: 10px; 
}

        </style>
    </head>
    <body>
        <div class="div1">
            This is the outer box.
            <div class="div2">
                This is the inner box.
            </div>
        </div>
    </body>
</html>