.flex {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
}
.flex-vertical-center {
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
}
.flex-horizontal-center {
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
}
.flex-all-center {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
}