Merging upstream version 5.3.3+dfsg.

Signed-off-by: Daniel Baumann <daniel@debian.org>

scss/_accordion.scss

@@ -20,7 +20,6 @@
   --#{$prefix}accordion-btn-icon-transform: #{$accordion-icon-transform};
   --#{$prefix}accordion-btn-icon-transition: #{$accordion-icon-transition};
   --#{$prefix}accordion-btn-active-icon: #{escape-svg($accordion-button-active-icon)};
-  --#{$prefix}accordion-btn-focus-border-color: #{$accordion-button-focus-border-color};
   --#{$prefix}accordion-btn-focus-box-shadow: #{$accordion-button-focus-box-shadow};
   --#{$prefix}accordion-body-padding-x: #{$accordion-body-padding-x};
   --#{$prefix}accordion-body-padding-y: #{$accordion-body-padding-y};
@@ -74,7 +73,6 @@
 
   &:focus {
     z-index: 3;
-    border-color: var(--#{$prefix}accordion-btn-focus-border-color);
     outline: 0;
     box-shadow: var(--#{$prefix}accordion-btn-focus-box-shadow);
   }
@@ -92,7 +90,7 @@
   &:first-of-type {
     @include border-top-radius(var(--#{$prefix}accordion-border-radius));
 
-    .accordion-button {
+    > .accordion-header .accordion-button {
       @include border-top-radius(var(--#{$prefix}accordion-inner-border-radius));
     }
   }
@@ -105,13 +103,13 @@
   &:last-of-type {
     @include border-bottom-radius(var(--#{$prefix}accordion-border-radius));
 
-    .accordion-button {
+    > .accordion-header .accordion-button {
       &.collapsed {
         @include border-bottom-radius(var(--#{$prefix}accordion-inner-border-radius));
       }
     }
 
-    .accordion-collapse {
+    > .accordion-collapse {
       @include border-bottom-radius(var(--#{$prefix}accordion-border-radius));
     }
   }
@@ -127,11 +125,7 @@
 // Remove borders and border-radius to keep accordion items edge-to-edge.
 
 .accordion-flush {
-  .accordion-collapse {
-    border-width: 0;
-  }
-
-  .accordion-item {
+  > .accordion-item {
     border-right: 0;
     border-left: 0;
     @include border-radius(0);
@@ -139,12 +133,18 @@
     &:first-child { border-top: 0; }
     &:last-child { border-bottom: 0; }
 
-    .accordion-button {
+    // stylelint-disable selector-max-class
+    > .accordion-header .accordion-button {
       &,
       &.collapsed {
         @include border-radius(0);
       }
     }
+    // stylelint-enable selector-max-class
+
+    > .accordion-collapse {
+      @include border-radius(0);
+    }
   }
 }