You can change background of page using html but Css is efficient and reliable way . In Css you can change background by changing color of page and particular position .One important things about css i.e css always use in between. Here is different ways
1.Background color
body{background-color:#36c;}
<h1 style=color:white;>Liveurlifehere blog
<p style=color:#f6f6f6;>This is an example of Css full page background change by Aman yadav
2.Set Background image
>Background image in full page
body{
background:url(‘IMAGE URL HERE‘);
}
Here body call to body word anywhere in the page and run this script.You can add style in only div for this you write style in that div like- Here you can add code for changing color or change background image.
>Background Image in fixed or small area
For changing background of small area you make table in that area and change the background in that particular area
<table style="background-image:url(UR IMAGE URL);">
Background iamge in small area