.image_de_garde {
  width: 1620px;
  height: 780px;
  margin: 0;
  padding: 0;
}

section,
h1 {
  display: flex;
  justify-content: center;
  margin: 0;
  padding: 0;
}

@media screen and (max-width: 1023px) {
  .image_de_garde {
    width: 1320px;
    height: 480px;
    margin: 25px 0 0 0;
  }

  body {
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
  }
}

@media screen and (max-width: 767px) {
  body {
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
  }
  .image_de_garde {
    width: 1120px;
    height: 280px;
    margin: 25px 0 0 0;
  }
}