从前：

.block {
  display: inline-block;
}
.block-left {
  display: block;
  float: left;
}
.block-right {
  display: block;
  float: right
}
.clearfix::after {
  content: '';
  display: none;
  clear: both;
  height: 0;
}

如今：

.block {
  display: flex;
  flex-flow: row nowrap;
  justify-content: space-between;
}
.block-left {
  display: inline
}
.block-right {
  display: inline
}