Js countdown code, when the mouse leaves the page and returns to the page, it will automatically stop and start_time and date

<title>Judge time based on mouse: Js countdown</title> <input type="button" id="downloadbtn" class="meng1an" onclick='if(timeout>0) {alert("Stop timing");return false;}document.location="#"; this.disabled=true;'>
[Ctrl A select all Note: If you need to introduce external Js, you need to refresh to execute

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