It is possible to add the shadow effect to the text in HTML only using CSS3. The “text-shadow” feature is used for this pupose.

The text-shadow property is used as follows:

text-shadow: 2px 3px 4px #0000FF;

 
This will produce text with a shadow 2px right and 3px below the text,which blurs for 4px. You can also mention the color for the shadow,then the shadow appears in the mentioned color(here it is #0000FF i.e. blue). This code should work in Firefox 3,safari 3+.

You can make a div tag for the text that you want to highlight, add this tag in CSS file.

Now,we take an example, suppose you want add shadow to a heading. So add a div tag around that heading.

  <div class="shadow_heading">
   HEADING
   </div>

In CSS file,add this:

   .shadow_heading {
   text-shadow: 2px 3px 4px #0000FF;    
   text-align:center;
    color:red;
    font-size:40px;
    }