ant-design/style/core/layouts.less

// Layout
.layout-fixed {
  .container-fixed();

  @media (min-width: @screen-sm-min) {
    width: @container-sm;
  }

  @media (min-width: @screen-md-min) {
    width: @container-md;
  }

  @media (min-width: @screen-lg-min) {
    width: @container-lg;
  }
}

.layout-fluid {
  .container-fixed()
}

// Grid system
.row {
  .make-row();
  display: block;
}

.row-flex {
  .make-row();
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;

  &:before,
  &:after {
    display: flex;
  }
}

.make-grid-columns();
.make-grid();