TML Print Preview issue, how to set some content does not appear on the Print preview page. How to control, there is code to see not very understand the explanation

Media properties for HTML <style> tags

HTML <style> Tags

Instance

Two different styles for two different media types (computer screen and print):

media="print">h1 {color: #000000;} p {color: #000000;} Body {background-color: #FFFFFF;} </style>
Try it yourself.
Definition and usage
The media property is used to specify different styles for different media types.
Tip: If you want to define more than one media type in a STYLE element, use a comma-delimited list (for example: <style type= "Text/css" media= "Screen,projection" >).
Browser support
All major browsers support the media property's "screen", "Print", and "all" values.
Note: Opera also supports "handheld" values.
Grammar
<style media= "value" >
Property value
 
 
 
  
  
 
   
 
    
value
 
    
Description
 
   
 
   
 
    
Screen
 
    
computer screen (default value).
 
   
 
   
 
    
Tty
 
    
A telex typewriter and a similar medium using an equal-width character grid.
 
   
 
   
 
    
Tv
 
    
TV type device (low resolution, limited screen tumbling capability).
 
   
 
   
 
    
Projection
 
    
Projector.
 
   
 
   
 
    
Handheld
 
    
Handheld Devices (small screen, limited bandwidth).
 
   
 
   
 
    
Print
 
    
Print Preview mode/print page.
 
   
 
   
 
    
Braille
 
    
The blind uses the word method to feed back the device.
 
   
 
   
 
    
Aural
 
    
Speech synthesizer.
 
   
 
   
 
    
All
 
    
Suitable for all devices.
 
   
 
  
 
 
 
TML Print Preview issue, how to set some content does not appear on the Print preview page. How to control, there is code to see not very understand the explanation