Warning, /plasma/breeze-gtk/src/gtk3/widgets/_treeview.scss is written in an unsupported language. File is not indexed.

 @charset "UTF-8";
 
 @mixin item-hover-middle {
         @if $new-highlight {
                 background-color: gtk("@theme_selected_bg_color");
                 border-left-color: gtk("@theme_selected_fg_color");
                 border-top-color: gtk("@theme_selected_fg_color");
         } @else {
                 background-color: gtkalpha(
                         gtk("@theme_selected_bg_color"),
                         0.3
                 );
                 border-left-color: gtk("@theme_fg_color");
                 border-top-color: gtk("@theme_fg_color");
         }
 }
 
 @mixin item-selected-middle {
         @if $new-highlight {
                 background-color: gtkalpha(
                         gtk("@theme_button_decoration_focus"),
                         0.3
                 );
                 color: gtk("@theme_button_foreground_active");
                 border: 1px solid gtk("@theme_button_decoration_focus");
                 border-left: 0;
                 border-right: 0;
                 border-radius: 0px;
         } @else {
                 background-color: gtk("@theme_selected_bg_color");
                 border-left-color: gtk("@theme_selected_fg_color");
                 border-top-color: gtk("@theme_selected_fg_color");
         }
 }
 
 @mixin item-selected-middle-backdrop {
         @if $new-highlight {
                 background-color: gtkalpha(
                         gtk("@theme_button_decoration_focus_backdrop"),
                         0.3
                 );
                 color: gtk("@theme_button_foreground_active_backdrop");
                 border: 1px
                         solid
                         gtk("@theme_button_decoration_focus_backdrop");
                 border-left: 0;
                 border-right: 0;
                 border-radius: 0px;
         } @else {
                 background-color: gtk(
                         "@theme_unfocused_selected_bg_color"
                 );
                 border-left-color: gtk(
                         "@theme_unfocused_selected_fg_color"
                 );
                 border-top-color: gtk(
                         "@theme_unfocused_selected_fg_color"
                 );
         }
 }
 
 /**************
  * Tree Views *
  **************/
 treeview.view {
         -GtkTreeview-grid-line-width: 0;
         -GtkTreeview-grid-line-pattern: "";
         -GtkTreeview-tree-line-width: 1;
         -GtkTreeview-tree-line-pattern: "";
         -GtkTreeview-expander-size: 16;
 
         border-left-color: gtk(
                 "@borders"
         ); // this is actually the tree lines color,
         border-top-color: transparent; // while this is the grid lines color, better then nothing
 
         rubberband {
                 @extend rubberband;
         } // to avoid borders being overridden by the previously set props
 
         &:selected {
                 border-radius: 0;
         } // rest border radius in lists
 
         &:hover {
                 @include item-hover-middle();
         }
 
         &:selected {
                 @include item-selected-middle();
         }
 
         &:backdrop:selected {
                 @include item-selected-middle-backdrop();
         }
 
         &:disabled {
                 color: gtk("@insensitive_fg_color");
                 &:selected {
                         color: gtk("@insensitive_selected_fg_color");
                         &:backdrop {
                                 color: gtk(
                                         "@insensitive_unfocused_selected_fg_color"
                                 );
                         }
                 }
                 &:backdrop {
                         color: gtk("@insensitive_unfocused_fg_color");
                 }
         }
         &.separator {
                 min-height: 2px;
                 color: gtk("@borders");
         }
         &.separator:backdrop {
                 color: gtk("@unfocused_borders");
         }
 
         &:backdrop {
                 border-left-color: gtk("@unfocused_borders");
         }
 
         &:drop(active) {
                 border-style: solid none;
                 border-width: 1px;
                 border-color: gtk("@theme_button_decoration_hover");
         }
 
         &.expander {
                 // GtkTreeView uses the larger of the expander’s min-width and min-height
                 min-width: 16px;
                 min-height: 16px;
                 -gtk-icon-source: -gtk-icontheme($arrow_right);
                 color: gtk("@theme_fg_color");
                 &:dir(rtl) {
                         -gtk-icon-source: -gtk-icontheme(
                                 "go-next-rtl-symbolic"
                         );
                 }
                 &:hover {
                         color: gtk("@theme_button_decoration_hover");
                 }
                 &:selected {
                         color: gtk("@theme_selected_fg_color");
                 }
                 &:checked {
                         -gtk-icon-source: -gtk-icontheme($arrow_down);
                         &:selected {
                                 color: gtk("@theme_selected_fg_color");
                         }
                 }
         }
         header {
                 button {
                         @extend %column_header_button;
                         color: gtk("@theme_button_foreground_normal");
                         background-color: gtk(
                                 "@theme_button_background_normal"
                         );
                         text-shadow: none;
                         box-shadow: none;
                         &:hover {
                                 @extend %column_header_button;
                                 color: gtk("@theme_button_foreground_normal");
                                 background-color: gtkalpha(
                                         gtk("@theme_button_decoration_hover"),
                                         0.5
                                 );
                                 box-shadow: none;
                         }
                         &:active {
                                 @extend %column_header_button;
                                 color: gtk("@theme_button_foreground_normal");
                                 background-color: gtkalpha(
                                         gtk("@theme_button_decoration_hover"),
                                         0.5
                                 );
                         }
                 }
                 button:last-child {
                         &:backdrop,
                         & {
                                 border-right-style: none;
                         }
                 }
         }
         button.dnd,
         header.button.dnd {
                 // for treeview-like derive widgets
                 &:active,
                 &:selected,
                 &:hover,
                 & {
                         padding: 0 6px;
                         color: gtk("@theme_selected_fg_color");
                         background-image: none;
                         background-color: gtk("@theme_selected_bg_color");
                         border-style: none;
                         border-radius: 0;
                         box-shadow: none;
                         text-shadow: none;
                 }
         }
 }
 
 %column_header_button {
         padding: 6px;
         border-style: none solid solid none;
         border-radius: 0;
         background-image: none;
         border-color: gtk("@borders");
         text-shadow: none;
         &:disabled {
                 border-color: gtk("@insensitive_borders");
                 color: gtk("@theme_button_foreground_insensitive");
                 background-color: gtk(
                         "@theme_button_background_insensitive"
                 );
                 background-image: none;
         }
         &:backdrop {
                 border-color: gtk("@unfocused_borders");
                 border-style: none solid solid none;
                 color: gtk("@theme_button_foreground_backdrop");
                 background-image: none;
                 background-color: gtk(
                         "@theme_button_background_backdrop"
                 );
                 &:disabled {
                         border-color: gtk("@unfocused_insensitive_borders");
                         background-image: none;
                         background-color: gtk(
                                 "@theme_button_background_backdrop_insensitive"
                         );
                         color: gtk(
                                 "@theme_button_foreground_backdrop_insensitive"
                         );
                 }
         }
 }