<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="index.css">
</head>
<body>
    <header>
        
    </header>
    <div class="wrapper">
    <aside>

    </aside>
    <nav>
        <div class="orange"></div>
        <div class="red"></div>
    </nav>

</div>
</body>
</html>
*{
    margin: 0;
    padding: 0;
}
header{
    height: 75px;
    background: blue;
}
aside{
    width: 335px;
    height: 447px;
    background: green;
    margin-top: 25px;
    margin-left: 50px;
}
.orange{
    width: 1125px;
    margin-top: 25px;
    margin-left: 40px;
    height: 107px;
    background: coral;
}
.red {
    width: 1125px;
    height: 713px;
    background: red;
    margin-left: 40px;
    margin-top: 20px;
}
.wrapper{
    display: flex;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.