How To Automatically Change Background color in your Blog

1. Click on Template from side bar. 
2. Then, you are supposed to click on Edit HTML.
3. Now click anywhere your blogger template coding and then Press Ctrl+F and you will have a search bar. Using that search bar, search for </head> in your blogger template and  paste the following code After </head> Tag.

Code - 1 >>>

<script src='http://ajax.googleapis.com/ajax/libs/jquery/1.5/jquery.min.js?ver=1.5' type='text/javascript'/>
<script type='text/javascript'>//<![CDATA[
function get_random_color(){var e="0123456789ABCDEF".split("");var t="#";for(var n=0;n<6;n++){t+=e[Math.round(Math.random()*14)]}return t}$(function(){$(".post").each(function(){$(this).css("background-color",get_random_color())})})//]]></script>

Note - Code-1 not work then try code-2

Code - 2 >>>

<script type='text/javascript'>//<![CDATA[
function get_random_color(){var e="0123456789ABCDEF".split("");var t="#";for(var n=0;n<6;n++){t+=e[Math.round(Math.random()*14)]}return t}$(function(){$(".post").each(function(){$(this).css("background-color",get_random_color())})})//]]></script>