How to use 2 ID CSS selectors in a rule

[sniperman]

I need to brush up on my CSS. I have a website powered by PHP which uses 2 templates.

The website is here http://insurancerestorationgroup.com.au/

The code on one page looks like this

<div id="header_index"> 
  <div id="logo">
  </div>
</div>

On the other it looks like this...

<div id="header"> 
  <div id="logo">
  </div>
</div>

I am trying to absolutely position the logo in different locations for each template to clear the header... but for some reason I cant use an ID selector beside an ID selector... here are my CSS rules.

#top_box_index {
	
	margin: 405px 0 30px 0;
	z-index: 5;
	
}

#header_index #top_box_index {
	
	margin: 405px 0 30px 0;
	z-index: 5;
	
}

#header #top_box_index {
	
	margin: 245px 0 30px 0;
	z-index: 5;
	
}

	#logo {
		
		float: left;
		position:absolute;
		top:550px;
		left:-240px;
		
	}

[sniperman]

Ok. Silly me.

#header #logo { }
#header_index #logo {}

I find theme editors hard to scroll in, hence, the wrong selectors in the first place!