Responsive Web Design Projects - Build a Product Landing Page

HTML-CSS
5 
 <style>
   #header {
     postion: fixed;
  width: 90px;
  height: 40px;
  float: left;
  padding-top: 1.7em;
}
    nav ul{
  float: right;
  margin-right: 1em;
}
nav li{
  display: inline;
  padding: 1em;
  display: inline-block;
}
  p {display: flex;}
    @media screen and (max-width: 600px) {
  body {
    background-color: grey;
  }
}
    </style>
    ```