Uniqiue background on every page - php

Question

I'm using Drupal 7. My bg image in page.tpl.php file and image get to css.
My html:
<div class="mainimage" id="mainimg" class="clearfix"></div>
And CSS:
#mainimg {
background: url("../img/mainimg.jpg") repeat scroll 0 0 transparent;
height: 500px;
left: 50%;
margin-left: -640px;
position: absolute;
width: 1280px;
z-index: 1;
top:0;
}
My bg image seen all pages. It's normally. But i want, change my bg image on every page.
E.G.
...
mysite.com/index.php -bg image: mainimg.jpg
mysite.com/news -bg image:news.jpg
mysite.com/about -bg image: about.jpg
...
How can i solve this?

Answer 1

You can use the built-in Drupal functions to add a unique identifier to the body, so you can target each page individually in your CSS.
For example, if the body had id="news", you could change the background image by adding this to your CSS:
#news #mainimg {
background-image: url("../img/news.jpg");
}

Answer 2

Use a different class per each page.
mysite.com/news
HTML
<div class="mainimage news-bg" id="mainimg" class="clearfix"></div>
CSS
.news-bg {
background: url("../img/news-bg.jpg") repeat scroll 0 0 transparent;
}
mysite.com/about
HTML
<div class="mainimage about-bg" id="mainimg" class="clearfix"></div>
CSS
.about-bg {
background: url("../img/about-bg.jpg") repeat scroll 0 0 transparent;
}

Answer 3

make the image php generated.
1) set header("content-type: image/jpg");
2) check from which page the request came and choose image
3) echo the binary data of your image.
Say this is in the file bg.php, you have to set background-image:url('bg.php');
Example:
function currentPageName() {
return substr($_SERVER["SCRIPT_NAME"],strrpos($_SERVER["SCRIPT_NAME"],"/")+1);
}
if(currentPageName() == "news.html")
$imagedata = file_get_contents('path/to/news.jpg');
//etc
header('Content-type: image/jpg');
echo $imagedata;