/*basic*/
html, body 
{ margin-top: 0;
  margin-bottom: 0;
  margin-left: 0;
  margin-right: 0;
  padding-left: 0;
  padding-right: 0;
	height:100%; /* this is the key! */
	background-color:#3399cc;
	font-family: Geneva, Arial, Verdana, sans-serif;
}
p{font size: 14pt;}
h1, h3{text-align:center;}
ul {list-style-type: square;
}
#header {
  margin: 20px;
  padding: 10px;
  height:20%;
	color: white;
	background-color: #6495ed;
}

#center {
  top: 180px;
	padding: 10px;
  margin-left: 100px;
  margin-right: 100px;
	background-color: white;
	height:80%; /* works only if parent container is assigned a height value */
	
}
#navigation ul { 
        margin: 0; 
        padding: 5px; 
        list-style-type: underline; 
        text-align: center; 
        background-color:#3399cc; 
        } 
 
#navigation ul li {  
        display: inline;
				font-size:14pt; 
        } 
 
#navigation ul li a { 
        text-decoration: none; 
        padding: .2em 1em; 
        color: white; 
        background-color: #3399cc; 
        } 
 
#navigation ul li a:hover { 
        color: #000; 
        background-color: white; 
        }