title: how to change the color of icon in carousel?
body: <p>I develop a function for <strong>carousel</strong>, I want to change the color of the icon <strong>(next-icon and previous-icon)</strong>, is it possible? and thnak's (i work with Angular 5)</p>
  
  <p>file.html: </p>
  
  <pre><code> &lt;ngb-carousel [interval]="3000"&gt; 
        &lt;ng-template ngbSlide&gt; ...  &lt;/ng-template&gt;
        &lt;ng-template ngbSlide&gt; ...  &lt;/ng-template&gt;
   &lt;/ngb-carousel&gt;
  </code></pre>
  
  <p>_carousel.css:</p>
  
  <pre><code>.carousel-control-prev-icon,
  .carousel-control-next-icon {
    display: inline-block;
    width: $carousel-control-icon-width;
    height: $carousel-control-icon-width;
    background: transparent no-repeat center center;
    background-size: 100% 100%;
  }
  .carousel-control-prev-icon {
    background-image: $carousel-control-prev-icon-bg;
  }
  .carousel-control-next-icon {
    background-image: $carousel-control-next-icon-bg;
  }
  </code></pre>
  
  <p>_variable.css:</p>
  
  <pre><code>$carousel-control-color:            $white !default;
  $carousel-control-width:            15% !default;
  $carousel-control-opacity:          .5 !default;
  
  $carousel-indicator-width:          30px !default;
  $carousel-indicator-height:         3px !default;
  $carousel-indicator-spacer:         3px !default;
  $carousel-indicator-active-bg:      $white !default;
  
  $carousel-caption-width:            70% !default;
  $carousel-caption-color:            $white !default;
  
  $carousel-control-icon-width:       20px !default;
  
  $carousel-control-prev-icon-bg:     str-replace(url("data:image/svg+xml;charset=utf8,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='#{$carousel-control-color}' viewBox='0 0 8 8'%3E%3Cpath d='M5.25 0l-4 4 4 4 1.5-1.5-2.5-2.5 2.5-2.5-1.5-1.5z'/%3E%3C/svg%3E"), "#", "%23") !default;
  $carousel-control-next-icon-bg:     str-replace(url("data:image/svg+xml;charset=utf8,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='#{$carousel-control-color}' viewBox='0 0 8 8'%3E%3Cpath d='M2.75 0l-1.5 1.5 2.5 2.5-2.5 2.5 1.5 1.5 4-4-4-4z'/%3E%3C/svg%3E"), "#", "%23") !default;
  
  $carousel-transition:               transform .6s ease !default;
  </code></pre>