@import url(reset.css);
.df {
  display: flex;
  justify-content: space-between;
}
.clearfix::after {
  content: '';
  display: block;
  height: 0;
  clear: both;
  visibility: hidden;
}
header,
main,
footer,
nav,
div[class*='_box'] {
  position: relative;
}
header::after,
main::after,
footer::after,
nav::after,
div[class*='_box']::after {
  content: '';
  display: block;
  height: 0;
  clear: both;
  visibility: hidden;
}
header::after,
main::after,
footer::after,
nav::after,
div[class*='_box']::after {
  content: '';
  display: block;
  height: 0;
  clear: both;
  visibility: hidden;
}