.flex {
  display: flex;
}

.flex-column {
  flex-direction: column;
}

.flex-row {
  flex-direction: row;
}

.flex-wrap {
  flex-wrap: wrap;
}

.flex-nowrap {
  flex-wrap: nowrap;
}

.flex-1 {
  flex: 1 1 0%;
}

.flex-auto {
  flex: 1 1 auto;
}

.flex-none {
  flex: none;
}

.justify-start {
  justify-content: flex-start;
}

.justify-end {
  justify-content: flex-end;
}

.justify-center {
  justify-content: center;
}

.justify-between {
  justify-content: space-between;
}

.justify-around {
  justify-content: space-around;
}

.justify-evenly {
  justify-content: space-evenly;
}

.items-start {
  align-items: flex-start;
}

.items-end {
  align-items: flex-end;
}

.items-center {
  align-items: center;
}

.items-baseline {
  align-items: baseline;
}

.items-stretch {
  align-items: stretch;
}

.self-start {
  align-self: flex-start;
}

.self-end {
  align-self: flex-end;
}

.self-center {
  align-self: center;
}

.self-stretch {
  align-self: stretch;
}

@media (min-width: 768px) {
  .flex-md-row {
    flex-direction: row;
  }
  
  .flex-md-column {
    flex-direction: column;
  }
}