#square
{
  width: 50px;
  height: 50px;
  background: gray;
}

#rectangle
{
  width: 100px;
  height: 50px;
  background: pink;
}

#diamond
{
  width: 50px;
  height: 50px;
  background: hotpink;
  transform: rotate(45deg);
}

#upsidedown
{
  width: 80px;
  height: 80px;
  background: lightblue;
  transform: rotate(180deg);
}

#circle {
  width: 100px;
  height: 100px;
  background: blue;
  border-radius: 50%;
}

#oval {
  width: 1000px;
  height: 50px;
  background: blue;
  border-radius: 50%;
}

#triangle {
  width: 0px;
  height: 0px;
  border-top: 50px solid red;
  border-left: 35px solid white;
  border-bottom: 0px solid yellow;
  border-right: 35px solid white;
}

#dtriangle {
  width: 0px;
  height: 0px;
  border-top: 50px solid red;
  border-left: 50px solid green;
  border-bottom: 50px solid yellow;
  border-right: 50px solid blue;
}

#trapezoid {
  width: 50px;
  height: 0px;
  border-top: 50px solid black;
  border-left: 25px solid white;
  border-right: 25px solid white;
}