Update _colors-libadwaita.scss

src/sass/gtk/_colors-libadwaita.scss

@@ -247,6 +247,9 @@ $dark_5: #000000;
     --accent-fg-color: @accent_fg_color;
   }
 
+  $selected_bg_color: gtkcolor(accent_bg_color);
+  $primary_color: gtkcolor(accent_bg_color);
+  $progress_color: gtkcolor(accent_bg_color);
   $selected_bg_color: gtkcolor(accent_bg_color);
   $primary_color: gtkcolor(accent_bg_color);
   $progress_color: gtkcolor(accent_bg_color);
@@ -286,8 +289,8 @@ $dark_5: #000000;
   $wm_border: gtkcolor(headerbar_darker_shade_color);
 
   @if $trans=='true' {
-    $bg_color: color-mix(in srgb, gtkcolor(window_bg_color) 95%, transparent);
+    $bg_color: color-mix(in srgb, gtkcolor(window_bg_color) 96%, transparent);
-    $dark_sidebar_bg: color-mix(in srgb, gtkcolor(sidebar_bg_color) 95%, transparent);
+    $dark_sidebar_bg: color-mix(in srgb, gtkcolor(sidebar_bg_color) 96%, transparent);
-    $menu_bg: color-mix(in srgb, gtkcolor(popover_bg_color) 95%, transparent);
+    $menu_bg: color-mix(in srgb, gtkcolor(popover_bg_color) 96%, transparent);
   }
 }

src/sass/gtk/_common-4.0.scss

@@ -1274,6 +1274,11 @@ splitbutton {
   }
 
   // Reimplementing linked so we don't blow up css
+  > button:not(:only-child):not(:first-child):not(:last-child),
+  > menubutton:not(:only-child):not(:first-child):not(:last-child) > button {
+    border-radius: 0;
+  }
+
   > button:dir(ltr),
   > menubutton > button:dir(rtl) {
     border-top-right-radius: 0;

src/sass/gtk/apps/_gnome-40.0.scss

@@ -1282,9 +1282,146 @@ window.background.csd {
   }
 }
 
+//
+// Builder
+//
+
+popover.background.global-search {
+  > arrow, > contents { padding: 0; }
+}
+
+popover.background.pages-popover {
+  listview > row {
+    padding: $base_padding;
+
+    button {
+      margin: 0;
+    }
+
+    check {
+      margin: 4px 2px;
+      -gtk-icon-size: 12px;
+    }
+  }
+}
+
+panelresizer .top-bar {
+  box-shadow: inset 0 -1px $borders_color;
+}
+
+.frameheader.header:not(.vertical) {
+  min-height: $medium_size;
+  padding: 0;
+  border: none;
+  border-bottom: 1px solid $borders_color;
+  background-color: color-mix(in srgb, black 6%, $base_color);
+
+  &:backdrop {
+    background-color: color-mix(in srgb, black 7%, $base_color);
+  }
+
+  tabbar.inline {
+    tabbox {
+      min-height: $medium_size;
+    }
+
+    .start-action {
+      padding: $container_padding / 2 $container_padding / 2 $container_padding / 2 $container_padding;
+    }
+
+    .end-action {
+      padding: $container_padding / 2 $container_padding $container_padding / 2 $container_padding / 2;
+    }
+  }
+}
+
+panelframeswitcher:not(.vertical) {
+  &.frameheader.header { padding: 0 $base_padding; }
+
+  > button.toggle.image-button {
+    border: none;
+    margin: $base_padding 0;
+  }
+}
+
+panelframeswitcher.frameheader.header.vertical {
+  > button.toggle.image-button {
+    min-height: 24px;
+    min-width: 24px;
+    padding: $base_padding;
+  }
+}
+
+panelstatusbar {
+  box-shadow: inset 0 1px $borders_color;
+
+  > menubutton > button,
+  > paneltogglebutton button {
+    border-radius: 0;
+    @extend %flat_button;
+  }
+}
+
+panelwidget entry.statusbar {
+  background-color: $bg_color;
+  border-radius: 0;
+  outline: none;
+  box-shadow: none;
+  border-top: 1px solid $borders_color;
+
+  &:focus-within {
+    outline: none;
+  }
+}
+
+.IdeTweaksWindow,
+.org-gnome-Builder {
+  .boxed-list {
+    box-shadow: inset 0 0 0 1px gtkalpha(currentColor, 0.08);
+  }
+}
+
+// Setting window
+.style-variant {
+  padding: 0 $base_padding * 2;
+
+  button.toggle {
+    padding: 0;
+
+    &, &:hover, &:focus, &:active, &:checked {
+      background: none;
+      outline: none;
+      border: none;
+      box-shadow: none;
+    }
+
+    > stylevariantpreview > .wallpaper {
+      border-radius: $bt_radius;
+      outline-color: transparent;
+      outline-width: 3px;
+      outline-offset: $base_padding / 2;
+      outline-style: solid;
+      box-shadow: none;
+    }
+
+    &:hover > stylevariantpreview > .wallpaper {
+      outline-color: gtkalpha(currentColor, 0.05);
+    }
+
+    &:active > stylevariantpreview > .wallpaper {
+      outline-color: gtkalpha(currentColor, 0.15);
+    }
+
+    &:checked > stylevariantpreview > .wallpaper {
+      outline-color: $primary_color;
+    }
+  }
+}
+
 //
 // Gnome extensions tool
 //
+
 popover.details-popover {
   .actions {
     border-spacing: 6px;