Transparent Image over an Iframe Tag

Guys, I want to create a page with HTML, CSS, JS, which will be like a Smartphone emulator, So, all the Touchable areas have been mapped from this website "https://www.image-map.net/" into an HTML file, It is inside the Iframe tag So could you please tell me how can I add a Transparent image of the Phone's skin over the iframe tag. I have a transparent image available. I wanted this "https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwjqk9WAr-nkAhXQZCsKHaTKBa4QjRx6BAgBEAQ&url=https%3A%2F%2Fiphone.apkpure.com%2Foptions-pro-screener%2Fcom.mobileinteractive.optionsphone&psig=AOvVaw38DiZ3n2CfKC4Ar1zvCtZ9&ust=1569411308893567" the content inside the Device Dummy should be iframe