Zvlastni css nechapu

Hi, dostal jsem po nekom jeden mensi projekt a css na ktere jsem zvyklej tam je udelany jinak nize uvadim kod:

@mixin theme()
{

    @for $i from $themeStart through $themeEnd 
    {
        .theme-#{$i} &
        {
            $g-themeColor: getThemeColor($i) !global;   
            $g-i: $i !global;

            @content;    
        }
    }

}

    @include theme()
    {
        .news-content
        {
            background: $g-themeColor;
        }

        .news-link
        {
            background: darken($g-themeColor, 12%);
        }

    }

.slider__section-name {@include fontSize(26); @include fontFamily(vagL);}

$message-types: (
  error   :  #b94a48,
  valid   :  #468847,
  warning :  #c09853,
  info    :  #3a87ad
) !default;

@each $type, $color in $message-types 
{
  .message-#{$type} 
  {
      @include message($color);
  }


a tak dale vubec tomu nerozumim jak v tom neco upravit?