html {
  height: 80%;
}
body {
  width: 800px;
  margin: 0 auto;
  padding-top: 5px;
  height: 100%;
}
header {
  background-color: grey;
  color: blue;
  text-align: center;
  font-style: italic;
  padding-right: 5px;
  font-size: 30px;
  display: block;
  width: 790px;
}

h2 {
  text-align: center;

}
nav a:link, a:visited {
      background-color: #808080;
      color: black;
      padding: 14px 20px;
      text-align: center;
      text-decoration: none;
      display: inline-block;
  }

nav a:hover, a:active {
      background-color: blue;
    }

p {
  text-align: center;
  padding-bottom: 30px;
}
img {
  display: block;
margin: auto;

}
ul {
  display: block;
}
div {
background-image: linear-gradient (green, blue);
backgound color: blue;
height: 200px;

}