html, body {
  margin: 0;
  padding: 0;
}

canvas {
  display: block;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 0;
}
html { 
  background-color: blue;
  color: orange;
}
.MainHeader { 
  text-align: center;
  font-style: italic;
  margin-top: 50px;
}

h1, h2, p{ 
  margin: 0;
}
.Part { 
background-color: red;
padding: 10px;
border: 1px solid black;
margin: 50px 0px 50px 0px;
}

#PartFive {
  background-color: antiquewhite;

}
body { 
  max-width: 600px;
  margin: auto;
  background-color: green;
}

img, video, audio, object {
  width: 100%;
  margin-top: 10px;
}
object { 
  aspect-ratio: 4/3;
}
.Nav a {
  color: violet; 
  text-decoration: none;
}
.Nav {
  position: fixed;
  top: 10px;
  right: 10px;
}

.Nav-list{
   list-style-type: none;
   padding: 0;
   margin: 0;
}
.Nav-item { 
  display: inline-block;
  background: black;
  padding: 5px;
}

/*blocks stack on top of each other. 
blocks automatically take up the whole width of the page. 
inline elements wrap and take up the space they need.*/