How can I embed a youtube video using variable widths/heights for a dynamic width web page?
I want to set a youtube video to 100% width so that it scales appropriately in a dynamic width column on a web page I am designing. 

The problem is that the height doesn't behave like the height of an image. Instead of scaling proportionately, it either collapses (if set to "auto" or left blank) or it scales seemingly random if set to a percentage.

How can I get it to remain proportionate while still dynamic?
How can I embed a youtube video using variable widths/heights for a dynamic width web page?
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I want to set a youtube video to 100% width so that it scales appropriately in a dynamic width column on a web page I am designing. 

The problem is that the height doesn't behave like the height of an image. Instead of scaling proportionately, it either collapses (if set to "auto" or left blank) or it scales seemingly random if set to a percentage.

How can I get it to remain proportionate while still dynamic?