Need help with CSS and JavaScript problem

I am using a CMS (Drupal) and do not have complete control of the div id statements for each 'node' of content (If I change one div tag of a certain type, the CMS changes all div tags of that type). I need to change the font size for certain div tags that are below a certain line in the HTML.

In other words, here is the psuedocode for what I need to do.

...

<font id='title'>...</font>
<font id='content'>...</font>

<font id='title'>...</font>
<font id='content'>...</font>

<font id='title'>...</font>
<font id='content'>...</font>

psuedocode: if ((id =='title' || id =='content') && (the tag is below this line)){change the font size to 60%} 

<font id='title'>...</font>
<font id='content'>...</font>

<font id='title'>...</font>
<font id='content'>...</font>

<font id='title'>...</font>
<font id='content'>...</font>

...

Code (markup):

 

You could use jQuery and perform a statement such as:

$("#title:gt(3)").addClass("largefontclass");
$("#content:gt(3)").addClass("largefontclass");

http://api.jquery.com/addClass/
http://api.jquery.com/gt-selector/

 

thank you foe this