header{
  min-height: 40px;
}

nav{  
  position: fixed;
  text-align: center;  
  display: block; 
  background-color: black;
  width: 650px;
  max-width: 100%;
}

ul li a{ 
  text-decoration: none; 
  color: white;
  text-align: center;  
  font-weight: bold;
}

ul li { 
  display: inline-block; 
  padding-right: 10px; 
  padding-left: 10px; 
}

body {
    font-family: helvetica, serif
}

#wrapper{
  margin: 0 auto;
  max-width: 650px;
  width: 100%;
  padding-right: 5px;
  padding-left: 5px;  
}

h1{
  font-family: helvetica,
  
}