sadly for the result..
I had tried your game made with unity and orientation is portrait.
this is the game presents in my mobile phone browser.
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and this is my settings
work well in the pc browser but mobile has problems.
my unity project settings resolution is 360*780
my mobile brower ua is phone, and my phone has locked the auto turn orientation.
not only my phone has that problems.my friends aslo has the same situation to my game.:(