Why the background increase in every click using $(document).height()?-CodePudding

I am using the $(document).height() to assign dynamically the height to a background.

Why occurs that when the document is clicked the background image increase it height? The document height is the same

function setDocumentHeight(){
  var height = $(document).height(); console.log("Document Height "   height);
  $(".bg").css({"height":height});
  
}
setDocumentHeight();
  
$(document).click(function(e) {
    if (e.button == 0) { setDocumentHeight(); }
});

https://jsfiddle.net/jd8n6qa9/

CodePudding user response：

set top and bottom 0 to absolute background. it will solve this issue.

.bg {top:0;bottom:0;}