Index: C:/xampp/htdocs/bootswatch-scss/paper/_bootswatch.scss.patch
===================================================================
--- C:/xampp/htdocs/bootswatch-scss/paper/_bootswatch.scss.patch
+++ C:/xampp/htdocs/bootswatch-scss/paper/_bootswatch.scss.patch
@@ -35,24 +35,32 @@
 }
 
 // Buttons ====================================================================
 
+$btn-bg-map: (
+    "default": $btn-default-bg,
+    "primary": $btn-primary-bg,
+    "success": $btn-success-bg,
+    "info": $btn-info-bg,
+    "warning": $btn-warning-bg,
+    "danger": $btn-danger-bg
+);
 @mixin btn($class){
+  .btn-#{$class} {
+    $bg: map-get($btn-bg-map, $class);
+    @include gradient-radial($bg 80%, darken($bg, 6%) 81%);
-  .btn-${class} {
-    $bg: "btn-${class}-bg";
-    @include gradient-radial($$bg 80%, darken($$bg, 6%) 81%);
     background-size: 200%;
     background-position: 50%;
     transition: background-size 2s;
 
     &:hover {
       background-size: 100%;
+      border-color: darken($bg, 6%);
-      border-color: darken($$bg, 6%);
     }
 
     &:active {
+      background-color: darken($bg, 6%);
+      @include gradient-radial(darken($bg, 6%) 10%, $bg 11%);
-      background-color: darken($$bg, 6%);
-      @include gradient-radial(darken($$bg, 6%) 10%, $$bg 11%);
       background-size: 1000%;
       @include box-shadow(2px 2px 2px rgba(0,0,0,.3));
     }
   }
@@ -276,9 +284,9 @@
     &:last-child {
       border-radius: 0 3px 3px 0;
     }
 
+    &:last-child.progress-bar:before {
-    &:last-child&:before {
       display: block;
       content: 'div::before';
       position: absolute;
       width: 100%;
@@ -288,21 +296,21 @@
       z-index: -1;
       background-color: lighten($progress-bar-bg, 35%);
     }
 
+    &-success:last-child.progress-bar:before {
-    &-success:last-child&:before {
       background-color: lighten($brand-success, 35%);
     }
 
+    &-info:last-child.progress-bar:before {
-    &-info:last-child&:before {
       background-color: lighten($brand-info, 45%);
     }
 
+    &-warning:last-child.progress-bar:before {
-    &-warning:last-child&:before {
       background-color: lighten($brand-warning, 35%);
     }
 
+    &-danger:last-child.progress-bar:before {
-    &-danger:last-child&:before {
       background-color: lighten($brand-danger, 25%);
     }
   }
 }