CSS without Mixin usage

gistfile1.css

-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;

opacity: .75; /* Standard: FF gt 1.5, Opera, Safari */
filter: alpha(opacity=75); /* IE lt 8 */
-ms-filter: "alpha(opacity=75)"; /* IE 8 */
-khtml-opacity: .75; /* Safari 1.x */
-moz-opacity: .75; /* FF lt 1.5, Netscape */

gistfile2.css

body {
  font: 12px Helvetica, Arial, sans-serif;
}
a.button {
  -webkit-border-radius: 5px;  
  -moz-border-radius: 5px;  
  border-radius: 5px;
}

gistfile3.yml

@import 'vendor'

body
  font 12px Helvetica, Arial, sans-serif  

a.button
  border-radius 5px

gistfile4.yml

font-size = 14px
font = (font-size * 2) "Lucida Grande", Arial

body
  font font sans-serif

gistfile5.css

body {
  font: 28px "Lucida Grande", Arial sans-serif;
}

gistfile8.txt

$ npm install stylus

Nested CSS Selectors

#header
  color #000000
  #logo
    color #A7A7A7

PHP as CSS Preprocessor

<?php 
$infobox_bg = '#FAF7B1';
$border_size = '5px';
?>
<?php function opacity($pct=50){ ?>
opacity: .<?php echo $pct ?>; /* Standard: FF gt 1.5, Opera, Safari */
filter: alpha(opacity=<?php echo $pct ?>); /* IE lt 8 */
-ms-filter: "alpha(opacity=<?php echo $pct ?>)"; /* IE 8 */
-khtml-opacity: .<?php echo $pct ?>; /* Safari 1.x */
-moz-opacity: .<?php echo $pct ?>; /* FF lt 1.5, Netscape */
<?php }?>

#content .infobox{
 <?php opacity(75) ?>
 background-color: <?php echo $infobox_bg ?>;
 border: <?php echo $border_size; ?> solid #000;
}

rendered output

#header{
  color: #000000;
}
#header #logo{
  color #A7A7A7
}