I am stuck on lesson 4 instruction 1 of unit 4. The program isn't showing me any error messages, but the instruction has a red x marked next to it. This is the code that I used. Please help me!!
<header clas="container"> <div class="row"> <h1 class="col-sm-4">Heading</h1> <nav class="col-sm-8 text-right"> <p>nav item 1</p> <p>nav item 2</p> <p>nav item 3</p> </nav> </div> </header>