Hey guys I've a download page with a button 'DOWNLOAD NOW'. When the button is clicked visitors will have to wait for the download to starts (doesn't redirect).

What I want is that sometimes it takes very long for the DL to start after clicking the button, for instance 10 seconds. Hence I want to show a simple preloader WHEN the button is click, while waiting for the browser to stop loading and download to start, AND hide the preloader when browser stop loading and download started.