Fixes #12937: Darken active button states just a smidge more

dist/css/bootstrap-rtl.css

@@ -3437,7 +3437,7 @@ fieldset[disabled] .btn {
 .btn-default.active,
 .open .dropdown-toggle.btn-default {
   color: #333;
-  background-color: #ebebeb;
+  background-color: #e6e6e6;
   border-color: #adadad;
 }
 
@@ -3483,7 +3483,7 @@ fieldset[disabled] .btn-default.active {
 .btn-primary.active,
 .open .dropdown-toggle.btn-primary {
   color: #fff;
-  background-color: #3276b1;
+  background-color: #3071a9;
   border-color: #285e8e;
 }
 
@@ -3529,7 +3529,7 @@ fieldset[disabled] .btn-primary.active {
 .btn-success.active,
 .open .dropdown-toggle.btn-success {
   color: #fff;
-  background-color: #47a447;
+  background-color: #449d44;
   border-color: #398439;
 }
 
@@ -3575,7 +3575,7 @@ fieldset[disabled] .btn-success.active {
 .btn-info.active,
 .open .dropdown-toggle.btn-info {
   color: #fff;
-  background-color: #39b3d7;
+  background-color: #31b0d5;
   border-color: #269abc;
 }
 
@@ -3621,7 +3621,7 @@ fieldset[disabled] .btn-info.active {
 .btn-warning.active,
 .open .dropdown-toggle.btn-warning {
   color: #fff;
-  background-color: #ed9c28;
+  background-color: #ec971f;
   border-color: #d58512;
 }
 
@@ -3667,7 +3667,7 @@ fieldset[disabled] .btn-warning.active {
 .btn-danger.active,
 .open .dropdown-toggle.btn-danger {
   color: #fff;
-  background-color: #d2322d;
+  background-color: #c9302c;
   border-color: #ac2925;
 }
 
@@ -4172,7 +4172,9 @@ tbody.collapse.in {
 
 [data-toggle="buttons"] > .btn > input[type="radio"],
 [data-toggle="buttons"] > .btn > input[type="checkbox"] {
-  display: none;
+  position: absolute;
+  z-index: -1;
+  opacity: 0;
 }
 
 .input-group {

dist/css/bootstrap.css

@@ -2676,7 +2676,7 @@ fieldset[disabled] .btn {
 .btn-default.active,
 .open .dropdown-toggle.btn-default {
   color: #333;
-  background-color: #ebebeb;
+  background-color: #e6e6e6;
   border-color: #adadad;
 }
 .btn-default:active,
@@ -2717,7 +2717,7 @@ fieldset[disabled] .btn-default.active {
 .btn-primary.active,
 .open .dropdown-toggle.btn-primary {
   color: #fff;
-  background-color: #3276b1;
+  background-color: #3071a9;
   border-color: #285e8e;
 }
 .btn-primary:active,
@@ -2758,7 +2758,7 @@ fieldset[disabled] .btn-primary.active {
 .btn-success.active,
 .open .dropdown-toggle.btn-success {
   color: #fff;
-  background-color: #47a447;
+  background-color: #449d44;
   border-color: #398439;
 }
 .btn-success:active,
@@ -2799,7 +2799,7 @@ fieldset[disabled] .btn-success.active {
 .btn-info.active,
 .open .dropdown-toggle.btn-info {
   color: #fff;
-  background-color: #39b3d7;
+  background-color: #31b0d5;
   border-color: #269abc;
 }
 .btn-info:active,
@@ -2840,7 +2840,7 @@ fieldset[disabled] .btn-info.active {
 .btn-warning.active,
 .open .dropdown-toggle.btn-warning {
   color: #fff;
-  background-color: #ed9c28;
+  background-color: #ec971f;
   border-color: #d58512;
 }
 .btn-warning:active,
@@ -2881,7 +2881,7 @@ fieldset[disabled] .btn-warning.active {
 .btn-danger.active,
 .open .dropdown-toggle.btn-danger {
   color: #fff;
-  background-color: #d2322d;
+  background-color: #c9302c;
   border-color: #ac2925;
 }
 .btn-danger:active,
@@ -3306,7 +3306,9 @@ tbody.collapse.in {
 }
 [data-toggle="buttons"] > .btn > input[type="radio"],
 [data-toggle="buttons"] > .btn > input[type="checkbox"] {
-  display: none;
+  position: absolute;
+  z-index: -1;
+  opacity: 0;
 }
 .input-group {
   position: relative;

less/mixins.less

@@ -530,7 +530,7 @@
   &.active,
   .open .dropdown-toggle& {
     color: @color;
-    background-color: darken(@background, 8%);
+    background-color: darken(@background, 10%);
         border-color: darken(@border, 12%);
   }
   &:active,