If you give body a background color in external stylesheetbody {background-color: red;}There is nothing there that will make it target a specific page.If you a apply id ref OR class to body element you can uniquely target that page, for example using a id ref.Page1<body id="bg-color01">Page2<body id="bg-color02">Page3<body id="bg-color03">Then target those id ref to apply different color to those specific pages,#bg-color01 {background-color: red;}#bg-color02 {background-color: green;}#bg-color03 {background-color: yellow;}IF you are able to insert style element within the <