style.css

 @import url('https://fonts.googleapis.com/css2?family=Poppins:wght@500;600;700');

*{
  margin: 0px;
  padding: 0px;
  font-family: "Poppins", sans-serif;
  font-weight: 700;
  box-sizing: border-box;
  cursor: none;
}

.container{
  background: #E8DDB5;
  display: flex;
  height: 100vh;
  justify-content: center;
  align-items: center;
}

button{
  border: 0px;
  outline: 0px;
  background: #745296;
  padding: 16px 32px;
  box-shadow: rgba(0, 0, 0, 0.2) 0px 10px 20px 0px;
  margin: 1rem 0;
  color: white;
}

.cursor{
  width: 50px;
  height: 50px;
  border: 3px solid white;
  border-radius: 50%;
  position: fixed;
  pointer-events: none;
  transform-origin: 100% 100%;
  transform: translate(-50%, -50%);
  mix-blend-mode: difference;
}

.scale-cursor{
  background: white;
}