@mixin dtb-two-stop-gradient($fromColor, $toColor) {
  background-color: $toColor; /* Fallback */
  background-image: -webkit-linear-gradient(top, $fromColor 0%, $toColor 100%); /* Chrome 10+, Saf5.1+, iOS 5+ */
  background-image: -moz-linear-gradient(top, $fromColor 0%, $toColor 100%); /* FF3.6 */
  background-image: -ms-linear-gradient(top, $fromColor 0%, $toColor 100%); /* IE10 */
  background-image: -o-linear-gradient(top, $fromColor 0%, $toColor 100%); /* Opera 11.10+ */
  background-image: linear-gradient(to bottom, $fromColor 0%, $toColor 100%);
  filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0, StartColorStr='#{nth( $fromColor, 1 )}', EndColorStr='#{nth( $toColor, 1 )}');
}

@mixin dtb-radial-gradient($fromColor, $toColor ) {
  background: $toColor; /* Fallback */
  background: -ms-radial-gradient(center, ellipse farthest-corner, $fromColor 0%, $toColor 100%); /* IE10 Consumer Preview */
  background: -moz-radial-gradient(center, ellipse farthest-corner, $fromColor 0%, $toColor 100%); /* Firefox */
  background: -o-radial-gradient(center, ellipse farthest-corner, $fromColor 0%, $toColor 100%); /* Opera */
  background: -webkit-gradient(radial, center center, 0, center center, 497, color-stop(0, $fromColor), color-stop(1, $toColor)); /* Webkit (Safari/Chrome 10) */
  background: -webkit-radial-gradient(center, ellipse farthest-corner, $fromColor 0%, $toColor 100%); /* Webkit (Chrome 11+) */
  background: radial-gradient(ellipse farthest-corner at center, $fromColor 0%, $toColor 100%); /* W3C Markup, IE10 Release Preview */
}

@mixin dtb-fixed-collection {
  // Fixed positioning feature
  &.fixed {
    position: fixed;
    top: 50%;
    left: 50%;
    margin-left: -75px;
    border-radius: 0;

    &.two-column {
      margin-left: -150px;
    }

    &.three-column {
      margin-left: -225px;
    }

    &.four-column {
      margin-left: -300px;
    }
  }

  // Multi-column layout feature
  -webkit-column-gap: 8px;
  -moz-column-gap: 8px;
  -ms-column-gap: 8px;
  -o-column-gap: 8px;
  column-gap: 8px;

  > * {
    -webkit-column-break-inside: avoid;
    break-inside: avoid;
  }

  &.two-column {
    width: 300px;
    padding-bottom: 1px;

    -webkit-column-count: 2;
    -moz-column-count: 2;
    -ms-column-count: 2;
    -o-column-count: 2;
    column-count: 2;
  }

  &.three-column {
    width: 450px;
    padding-bottom: 1px;

    -webkit-column-count: 3;
    -moz-column-count: 3;
    -ms-column-count: 3;
    -o-column-count: 3;
    column-count: 3;
  }

  &.four-column {
    width: 600px;
    padding-bottom: 1px;

    -webkit-column-count: 4;
    -moz-column-count: 4;
    -ms-column-count: 4;
    -o-column-count: 4;
    column-count: 4;
  }
}

@mixin dtb-processing {
  color: rgba(0, 0, 0, 0.2);

  &:after {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 16px;
    height: 16px;
    margin: -8px 0 0 -8px;
    box-sizing: border-box;

    display: block;
    content: ' ';
    border: 2px solid rgb(40, 40, 40);
    border-radius: 50%;
    border-left-color: transparent;
    border-right-color: transparent;
    animation: dtb-spinner 1500ms infinite linear;
    -o-animation: dtb-spinner 1500ms infinite linear;
    -ms-animation: dtb-spinner 1500ms infinite linear;
    -webkit-animation: dtb-spinner 1500ms infinite linear;
    -moz-animation: dtb-spinner 1500ms infinite linear;
  }
}

@keyframes dtb-spinner {
  100% {
    transform: rotate(360deg);
  }
}

@-o-keyframes dtb-spinner {
  100% {
    -o-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}

@-ms-keyframes dtb-spinner {
  100% {
    -ms-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}

@-webkit-keyframes dtb-spinner {
  100% {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}

@-moz-keyframes dtb-spinner {
  100% {
    -moz-transform: rotate(360deg);
    transform: rotate(360deg);
  }
}