what type of sleepers are on the D903 Beijing to Guangzhou?

They are double deck berths set along the aisle lengthwise like the new type sleepers on this page. BTW, due to the limited space, it is not recommended to big guys.

Steve, the D903 has changed to another train earlier in this July. The sleepers on present D903 are not arranged lengthwise, but like sleepers on most other trains: two double-deck birth in each cabin with a sliding door. You can see the first picture on this page.