@mixin linearGradientV($property_name, $top, $bottom, $top_position: 0%, $bottom_position: 100%){
    #{$property_name}: $top; /* Old browsers */
    #{$property_name}: -moz-linear-gradient(top,  $top $top_position, $bottom $bottom_position); /* FF3.6+ */
    #{$property_name}: -webkit-linear-gradient(top,  $top $top_position,$bottom $bottom_position); /* Chrome10+,Safari5.1+ */
    #{$property_name}: -o-linear-gradient(top,  $top $top_position,$bottom $bottom_position); /* Opera 11.10+ */
    #{$property_name}: -ms-linear-gradient(top,  $top $top_position,$bottom $bottom_position); /* IE10+ */
    #{$property_name}: linear-gradient(to bottom,  $top $top_position,$bottom $bottom_position); /* W3C */
}

@mixin linearGradientH($property_name, $left, $right, $left_position: 0%, $right_position: 100%){
    #{$property_name}: $left; /* Old browsers */
    #{$property_name}: -moz-linear-gradient(left,  $left $left_position, $right $right_position); /* FF3.6+ */
    #{$property_name}: -webkit-linear-gradient(left,  $left $left_position,$right $right_position); /* Chrome10+,Safari5.1+ */
    #{$property_name}: -o-linear-gradient(left,  $left $left_position,$right $right_position); /* Opera 11.10+ */
    #{$property_name}: -ms-linear-gradient(left,  $left $left_position,$right $right_position); /* IE10+ */
    #{$property_name}: linear-gradient(to right,  $left $left_position,$right $right_position); /* W3C */
}

@mixin venderPrefix($property_name, $value) {
  #{$property_name}: $value;
  -webkit-#{$property_name}: $value;
  -moz-#{$property_name}: $value;
  -ms-#{$property_name}: $value;
  -o-#{$property_name}: $value;
}
