amis/packages/amis-ui/scss/layout/_vbox.scss

.#{$ns}Vbox {
  display: table;
  border-spacing: 0;
  position: relative;
  width: 100%;
  height: 100%;
  min-height: 240px;

  & .row-row {
    display: table-row;
    height: 100%;

    & .#{$ns}Vbox-cell {
      position: relative;
      height: 100%;
      width: 100%;

      .ie & {
        display: table-cell;
        overflow: auto;

        & .cell-inner {
          overflow: visible !important;
        }
      }

      & .cell-inner {
        position: absolute;
        top: 0;
        bottom: 0;
        left: 0;
        right: 0;
        -webkit-overflow-scrolling: touch;
        overflow: auto;
      }
    }
  }
}