I’m glad I could help you with your html for YouTube. :)
I was trying to use a reduced size YouTube embed as a television set in a cartoon. I had not thought of defining a table the size of the cartoon and use the cartoon as the table background. Then place the embed in the upper right hand corner of a cell or lower left hand corner depending on how the cell is vertically aligned and using the cell width and height to position it anywhere on the cartoon. I have tried different screen and page text size settings and so far it works for everything that I have tried. I think it will always display correctly.