body{
  margin:0;
  padding:0;
}
.container{
  position:relative;
  width:100%;
}
.container .section{
  position:sticky;
  top:0;
  width:100%;
  height:100vh;
  background:#000;
}
.container .section:nth-child(1){
  background: url(https://subjects.netlify.app/mathematics/res/matrix%20multiplication.png);
  background-size:cover;
}
.container .section:nth-child(2){
  background: url(https://subjects.netlify.app/mathematics/res/derivative%20calculator.png);
  background-size:cover;
}
.container .section:nth-child(3){
  background: url(https://subjects.netlify.app/mathematics/res/quadratic%20equation%20solver%20default.png);
  background-size:cover;
}
.container .section:nth-child(4){
  background: url(https://subjects.netlify.app/mathematics/res/quadratic%20equation%20solver%201.png);
  background-size:cover;
}
.container .section:nth-child(5){
  background: url(https://subjects.netlify.app/mathematics/res/quadratic%20equation%20solver%202.png);
  background-size:cover;
}
.container .section:nth-child(6){
  background: url(https://subjects.netlify.app/mathematics/res/star%20triangle.png);
  background-size:cover;
}
.container .section:nth-child(7){
  background: url(https://subjects.netlify.app/mathematics/res/ABC%20=%20A!%20+%20B!%20+%20C!.png);
  background-size:cover;
}
.container .section:nth-child(8){
  background: url(https://subjects.netlify.app/mathematics/1ton.png);
  background-size:cover;
}
.container .section:nth-child(9){
  background: url(https://subjects.netlify.app/mathematics/res/math%20graphs.png);
  background-size:cover;
}