nav{
    position: fixed;
    background-color: white;
    width: 100%;
    opacity: 1;
    height:70px;
    z-index: 2;
    top: 0;
 
    
}

body{
    
    
}

h1.first-header{
    font-size: 30px;
    font-weight: 200;
    text-align: center;
    color: black;
    margin-top:0;
}

h1{
    
    font-size:30px;
    font-weight: 900;
        
}



body{ margin-top: 125px; }

.gfx{
    width: 100%;
    
}


section{
    width: 2000px;
    min-height: 600px;
}

ul{
  list-style: none;
  text-align:center;
    margin-top: -23px;
}

li{ 
    display: inline-block; 
    font-size:20px; 
    padding:5px;
}



a {
    text-decoration: none;
    color:black;
   
}

a:hover {
  opacity: 0.6;

}




#one {

   background-color:red;
    height: 800px;
   
}
#two{
     background-color:yellow;
     height: 800px;
       
}
#three{
     background-color:blue;
        height: 800px;
}
#four{
     background-color:orange;
     height: 800px;
       
}