message: style(Pagination): improve text size adjust
diff: .van-pagination {
  display: flex;
  font-size: @pagination-font-size;
  - line-height: @pagination-height;
  - text-align: center;
  +
  + &__item,
  + &__page-desc {
  + display: flex;
  + align-items: center;
  + justify-content: center;
  + }
  &__item {
  flex: 1;
  