I am having problems getting css to modify the <div id="wrapper">.

Here is the code copy and pasted over. I can't seem to find out what the problem is. It looks like I copied verbatim.

The style sheet is saved The HTML doc is saved Tags are closed

</header> <div id="wrapper"> <section>
<ul> <li> <a href="img/numbers-01.jpg"> <img src="img/numbers-01.jpg" alt=""> <p> Experimentation with color and texture.</p>
</a>
</li>
<li> <a href="img/numbers-02.jpg"> <img src="img/numbers-02.jpg" alt=""> <p>Playing with blending modes in Photoshop.</p>
</a>
</li> <li> <a href="img/numbers-06.jpg"> <img src="img/numbers-06.jpg" alt=""> <p>Trying to create an 80's style of glows.</p>
</a>
</li> <li> <a href="img/numbers-09.jpg"> <img src="img/numbers-09.jpg" alt=""> <p>Drips created using Photoshop brushes.</p>
</a>
</li> <li> <a href="img/numbers-12.jpg"> <img src="img/numbers-12.jpg" alt=""> <p>Creating shapes using repetition.</p>
</a>
</li> </ul> </section>
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