.before_image {
  margin-bottom: 0;
}

#start_section_1 {
  height: 10vw;
}

@media (orientation: portrait) {
  .img_fulldisplay {
    width: 90vw;
    border: 2px solid black;
    border-radius: 3vw;
  }

  #start_section_1 {
    height: 20vw;
  }

  #start_theory {
    height: 17vw;
  }

  #header .link_box {
    padding-left: 1.8vw;
    padding-right: 1.8vw;
  }

  #header .link_box p {
    font-size: 4.5vw;
  }
}