sung.css

header{
    color: lightgray;
    background-color: black;
    text-align: center;
    font-size: 40px;
    display: block;

}
body {
    background-color: lightgray;
    position: relative;
    width: 100%;

    display: block;
  }

  body > *  {
    margin: auto;
    width: 800px;
    display: block;
    overflow: auto;
  }

  body > script {
    display: none
  }
nav ul{
    margin: 0;
    padding:0;
    list-style: none;
}

nav ul li {
    display: inline-block;
    margin: 20px;
    font-size: 20px;
    }
img {
    width: 400px;
    border: 2px solid black;
    text-align: center;
}
section{
    margin: auto;
    width: 500px;
    display: block;
    overflow: auto;
}
img{ 
    display:block;
    margin-left: auto;
    margin-right:auto;
}
h2{
    text-align: center;
    
}
h3 {
    text-align: center;
}
.test {
    margin-top: 10px;
    text-align: center;
}