feat(themes): theme builder app updates

* theme-builder wip

* Theme Builder updates
- new CSS variable support
- realtime color updating with alpha support (rgb generation)
- auto tint/shade/contrast generation
- auto step generation
- CSS variable highlighting (forward and backwards)
- Colourlovers Palette search (via local proxy)

packages/core/src/components/button/button.ios.scss

@@ -34,6 +34,13 @@
   opacity: $button-ios-opacity-hover;
 }
 
+a[disabled],
+button[disabled],
+.button[disabled] {
+  opacity: $button-ios-opacity-disabled;
+}
+
+
 // iOS Default Button Color Mixin
 // --------------------------------------------------
 

packages/core/src/components/button/button.ios.vars.scss

@@ -57,6 +57,9 @@ $button-ios-opacity-hover:                          .8 !default;
 /// @prop - Background color of the focused button
 $button-ios-background-color-focused:               ion-color($colors-ios, $button-ios-background-color, shade, ios) !default;
 
+/// @prop - Opacity of the button when disabled
+$button-ios-opacity-disabled:                       $alpha-ios-medium !default;
+
 
 // iOS Large Button
 // --------------------------------------------------

packages/core/src/components/button/button.md.scss

@@ -46,6 +46,11 @@
   background-color: $button-md-text-color;
 }
 
+a[disabled],
+button[disabled],
+.button[disabled] {
+  opacity: $button-md-opacity-disabled;
+}
 
 // Material Design Default Button Color Mixin
 // --------------------------------------------------

packages/core/src/components/button/button.md.vars.scss

@@ -78,6 +78,9 @@ $button-md-ripple-background-color:       $text-md-color-step-200 !default;
 /// @prop - Background color of the focused button
 $button-md-background-color-focused:       ion-color($colors-md, $button-md-background-color, shade, md) !default;
 
+/// @prop - Opacity of the button when disabled
+$button-md-opacity-disabled:               $alpha-md-medium !default;
+
 
 // Material Design Large Button
 // --------------------------------------------------

packages/core/src/components/button/button.scss

@@ -57,7 +57,6 @@ a[disabled],
 button[disabled],
 .button[disabled] {
   cursor: default;
-  opacity: .4;
 
   pointer-events: none;
 }