Color:

A layer of 60 long [bold thickening]]

A layer of 70 long [bold thickening]]

A layer of 80 long [bold thickening]]

The second floor is 60 long [bold and thickened]]

The second floor is 70 long [bold and thickened]]

The second floor is 80 long [bold and thickened]]

Three-layer 60 long [bold thickening]]

Three layers 70 long [bold and thickened]]

Three layers 80 long [bold and thickened]]

Four layers 60 long [bold and thickened]]

Four layers 70 long [bold and thickened]]

Four layers 80 long [bold and thickened]]

Five-layer 60 long [bold thickening]]

Five layers 70 long [bold and thickened]]

Five layers 80 long [bold and thickened]]