For full visuaforce page we can use renderas attribute..then how to convert the half of the visualforce page into pdf?please give answer with code..

After reading the documentation I did following

1. created sample CSS file named customStyles.css:

<style type="text/css">
body { background-image: url("images/SFSummary.gif") }
</style>

 2. Zipped up the images folder and customStyles.css together as myStyles.zip

 3.  Uploaded myStyles.zip as Static Resources with the name myStyles

 4. Referenced the stylesheet in visualforce page:

<apex:page standardController="Mileage__c" extensions="MileageExtension" tabStyle="Mileage_Custom_View__tab" standardStylesheets="false" >
<apex:stylesheet value="{!URLFOR($Resource.myStyles, 'customStyles.css')}"/>
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