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مازول زیر را ببینید :
http://extensions.joomla.org/extensions/style-a-design/typography/8295
Front-end Font Size Adjuster - 6 colors or Custom Text!
This module allows the user of your Web site to increase or decrease the font size of the site. New: works with px, em, and pt! The JavaScript stores a cookie in the visitor's browser that remembers the visitors font size setting. This module allows you to pick from six different buttons in various colors or text only with the back-end module params.
You can assign a class to the module in the back-end params allowing you to custom style the plain text or even image option. The advantage to the plain text option, is that you can custom style to any font-family or color to fit your site best with a class and your stylesheet.
This module includes transparent Black Text and Transparent White Text Options which allow the module to seamlessly fit your Site. The transparent buttons are your choice of png or gif images. png images provide a higher quality look, however Internet Explorer 6 and earlier have trouble reading png images properly. If you have much IE6 traffic and you want transparent buttons, you should use either the text option or the gif images.
NOTICE: THIS MODULE WILL NOT ADJUST THE FONT SIZE IF YOU USE INLINE STYLES OR FONT SIZES CREATED BY A TINY MCE EDITOR. IF YOU UNIVERSALLY CONTROL YOUR FONT SIZE WITH YOUR CSS, THIS MODULE WILL WORK PERFECT! If this module does not work with your site, there is a font-size style that is taking precedence over this module. We have a tutorial showing how to overcome this issue.
This is not a hack and is incredibly easy to setup or disable.
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