@mixin blur($radius) {
  -webkit-filter: blur($radius);
  -moz-filter: blur($radius);
  -o-filter: blur($radius);
  -ms-filter: blur($radius);
  filter: blur($radius);
}

@mixin radial-gradient($colorcenter, $colorside) {
    background: -webkit-radial-gradient($colorcenter, $colorside);
    background:    -moz-radial-gradient($colorcenter, $colorside);
    background:     -ms-radial-gradient($colorcenter, $colorside);
    background:      -o-radial-gradient($colorcenter, $colorside);
    background:         radial-gradient($colorcenter, $colorside);
}

@mixin background-color-opacity($color, $opacity: 0.3) {
    background-color: $color; /* The Fallback */
    background-color: rgba($color, $opacity);
}