* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-size: 100%;
  font-weight: normal;
  font-style: normal;
}

body {
  background-image: url("inter.jpg");
  background-size: cover;
}

iframe {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.뒤로 {
  text-decoration: none;
  position: fixed;
  right: 80px;
  bottom: 80px;
  font-size: 50px;
}