discourse/app/assets/stylesheets/common/base/onebox.scss

a.loading-onebox {
  background: {
    image: image-url("spinner_96.gif");
    position: 0;
    size: 20px;
    height: 25px;
    repeat: no-repeat;
  };
  padding-left: 25px;
}


.onebox-result {
  margin-top: 15px;
  padding: 12px 25px 12px 12px;
  border-left: 5px solid $primary_border_color;
  background: lighten($secondary_background_color, 76%);
  font-size: 14px;
  > .source {
    margin-bottom: 12px;
    margin-right: 10px;
    display: block;
    color: $primary_text_color;
    position: relative;
    height: 20px;
    .info {
      a {
        color: black;
        text-decoration: none;
        padding-right: 10px;
      }
      position: absolute;
      font-size: 14px;
      img.favicon {
        margin-right: 3px;
      }
    }
  }


  .onebox-result-body {
    padding-top: 5px;
    img {
      max-height: 80%;
      max-width: 25%;
      height: auto;
      float: left;
      margin-right: 10px;
    }
    h3, h4 {
      margin: 0 !important;
    }
    code {
      max-height: 400px;
    }
    .metrics {
      clear: both;
      padding-bottom: 25px;
      .metric {
        display: inline-block;
        padding-left: 33px;
        float: left;
      }
    }
  }
}

// RottenTomatoes Onebox
.onebox-result {
  .onebox-result-body {
    img.verdict {
      float: none;
      margin-right: 7px;
    }
    img.popcorn {
      float: none;
      margin-left: 20px;
      margin-right: 5px;
    }
  }
}

@mixin onebox-favicon($class, $image) {
  &.#{$class} .source {
    background-image: image-url("favicons/#{$image}.png");
    background-repeat: no-repeat;
    padding-left: 20px;
  }
}

aside.onebox {
  margin-top: 15px;
  padding: 12px 25px 12px 12px;
  border-left: 5px solid $primary_border_color;
  background: lighten($secondary_background_color, 76%);
  font-size: 14px;

  header {
    a[href] {
      color: $primary_text_color;
      text-decoration: none;
    }
  }

  @include onebox-favicon('stackexchange', 'stackexchange');
  @include onebox-favicon('twitterstatus', 'twitter');
  @include onebox-favicon('wikipedia', 'wikipedia');
  @include onebox-favicon('githubblob', 'github');
  @include onebox-favicon('amazon', 'amazon');


  .onebox-body {
    clear: both;

    h3, h4 {
      font-size: 1.17em;
      margin: 10px 0 !important;
    }

    a[href] {
      color: $link_color;
      text-decoration: none;
    }

    a[href]:visited {
      color: $link_color;
    }

    img {
      max-height: 80%;
      max-width: 25%;
      height: auto;
      float: left;
      margin-right: 10px;
    }
  }
}

.onebox-avatar {
  height: 90px;
  width: 90px;
}