title: How to place a nav bar so that it floats on top of an image?
body: <p>Hi I am trying to place a simple horizontal navigation bar so as that it floats on top (in the bottom left corner
  to be precise) of a header. The header is an image of a simple color gradient and is inside of a div. The code
  for the nav bar is placed inside of this in another div, but always appears beneath the header. 
  Here is the html:</p>
  
  <pre><code>&lt;div&gt;
      &lt;img id="Header" src="images/header.jpg"/&gt;
      &lt;div&gt;   
          &lt;ul id="nav"&gt;
              &lt;li&gt;&lt;a href="#"&gt;About Us&lt;/a&gt;&lt;/li&gt;
              &lt;li&gt;&lt;a href="#"&gt;Our Products&lt;/a&gt;&lt;/li&gt;
              &lt;li&gt;&lt;a href="#"&gt;FAQs&lt;/a&gt;&lt;/li&gt;
              &lt;li&gt;&lt;a href="#"&gt;Contact&lt;/a&gt;&lt;/li&gt;
              &lt;li&gt;&lt;a href="#"&gt;Login&lt;/a&gt;&lt;/li&gt;
          &lt;/ul&gt;
      &lt;/div&gt;
  &lt;/div&gt;  
  &lt;img id="Decal" src="images/decal.png"/&gt;
  </code></pre>
  
  <p>And the relavent CSS:</p>
  
  <pre><code>#Header {
  height:205px;
  width: 100%;
  z-index:1;
  }
  
  #Decal {
  position: absolute;
  z-index: 2;
  right: 5px;
  top: 1px;
  }
  #nav {
  width: 100%;
  float: left;
  margin: 0 0 3em 0;
  padding: 0;
  list-style: none;
  background-color: #f2f2f2;
  border-bottom: 1px solid #ccc; 
  border-top: 1px solid #ccc; }
  #nav li {
  float: left; }
  #nav li a {
  display: block;
  padding: 8px 15px;
  text-decoration: none;
  font-weight: bold;
  color: #069;
  border-right: 1px solid #ccc; }
  #nav li a:hover {
  color: #c00;
  background-color: #fff; }
  </code></pre>
  
  <p>This has been bugging me for quite awhile so any help is greatly appreciated thanks!</p>