(HTML) Document 01 & 02: Background color for figures

[anermina]

Document 01:
Specification: image size is clearly different in some areas (also the background is a grey colour, is this a specification?)​

　　→ The background is also grey in other parts of the image, possibly due to the use of metanorma or pattern B.​

Document 02:
Specification: grey background on diagram → is the background grey using metanorma or Pattern B​

9th and 73rd comment from Plateau team

[ronaldtse]

This is to do with HTML styling, we will handle once it is confirmed.