Hi sajads
Try in this way
Goto Extensions -> templates -> templates -> select your template -> click on Create Overrides tab then select the mod_jasidenews
Goto /templates/yourtemplate/html/mod_jasidenews
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edit this file default.php and find :
<?php if ($descMaxChars!=0) : ?>
<?php echo $helper->trimString( strip_tags($item->introtext), $descMaxChars); ?>
<?php endif;?>
Change it to
<?php if ($descMaxChars!=0) : ?>
<span class="ja-sidenews-font"><?php echo $helper->trimString( strip_tags($item->introtext), $descMaxChars); ?></span>
<?php endif;?>
Then add to your custom.css file in this folder /templates/yourtemplate/css/
.ja-sidenews-font {
font-family:yourfont;
}
Hope it helps