Remove redundant properties & nullify redundant percentages

scss/mixins/_gradients.scss

@@ -17,33 +17,31 @@
 // Creates two color stops, start and end, by specifying a color and position for each color stop.
 @mixin gradient-x($start-color: $gray-700, $end-color: $gray-800, $start-percent: 0%, $end-percent: 100%) {
   background-image: linear-gradient(to right, $start-color $start-percent, $end-color $end-percent);
-  background-repeat: repeat-x;
 }
 
 // Vertical gradient, from top to bottom
 //
 // Creates two color stops, start and end, by specifying a color and position for each color stop.
-@mixin gradient-y($start-color: $gray-700, $end-color: $gray-800, $start-percent: 0%, $end-percent: 100%) {
+@mixin gradient-y($start-color: $gray-700, $end-color: $gray-800, $start-percent: null, $end-percent: null) {
   background-image: linear-gradient(to bottom, $start-color $start-percent, $end-color $end-percent);
-  background-repeat: repeat-x;
 }
 
 @mixin gradient-directional($start-color: $gray-700, $end-color: $gray-800, $deg: 45deg) {
   background-image: linear-gradient($deg, $start-color, $end-color);
-  background-repeat: repeat-x;
 }
+
 @mixin gradient-x-three-colors($start-color: $blue, $mid-color: $purple, $color-stop: 50%, $end-color: $red) {
   background-image: linear-gradient(to right, $start-color, $mid-color $color-stop, $end-color);
-  background-repeat: no-repeat;
 }
+
 @mixin gradient-y-three-colors($start-color: $blue, $mid-color: $purple, $color-stop: 50%, $end-color: $red) {
   background-image: linear-gradient($start-color, $mid-color $color-stop, $end-color);
-  background-repeat: no-repeat;
 }
+
 @mixin gradient-radial($inner-color: $gray-700, $outer-color: $gray-800) {
   background-image: radial-gradient(circle, $inner-color, $outer-color);
-  background-repeat: no-repeat;
 }
+
 @mixin gradient-striped($color: rgba($white, .15), $angle: 45deg) {
   background-image: linear-gradient($angle, $color 25%, transparent 25%, transparent 50%, $color 50%, $color 75%, transparent 75%, transparent);
 }