.{
  margin: 0;
  padding: 0;
}

html, body {
  width: 100%;
  height: 100%;
  font-size: 14px;
  font-weight: normal;
  color: blue:
}

.background {
  width: 100%;
  height: 100%;
  background-image:url(../image/creativity.jpg);
  background-repeat: no-repeat;
  background-size: cover;
  background-color: grey;
  position: relative;
  overflow-y: auto;
}

 .nav {
   width: 300px;
   height: auto;
   position: sticky;
   top: 10%;
   left: 0;
 }

.nav a {
  text-decoration: none;
  font-size: 30px;
  font-family: verdana;
  font-weight: lighter;
  width: 300px;
  height: 100px;
  margin: 5px;
  float: left;
  display:inline-block;
  background-color: black;
  color: white;
  line-height: 90px;
  text-align: center;
}