Bootstrap（FlexBox）一部

bootstrap-flexbox.css

/* Flex */
.d-flex{
  display : flex;
}
.d-inline-flex{
  display : inline-flex;
}

/* Direction */
.flex-row{
  flex-direction : row; 
}
.flex-row-reverse{
  flex-direction : row-reverse; 
}
.flex-column{
  flex-direction : column;
}
.flex-column-reverse{
  flex-direction : column-reverse;
}

/* Justify content */
.justify-content-start{
  justify-content : flex-start;
}
.justify-content-end{
  justify-content : flex-end;
}
.justify-content-center{
  justify-content : center;
}
.justify-content-between{
  justify-content : space-between;
}
.justify-content-around{
  justify-content : space-around;
}

/* Align items */
.align-items-start{
  align-items : flex-start;
}
.align-items-end{
  align-items : flex-end;
}
.align-items-center{
  align-items : center;
}
.align-items-baseline{
  align-items : baseline;
}
.align-items-stretch{
  align-items : stretch;
}