horst3180_arc-theme/common/gtk-3.0/3.16/_transparent_widgets.scss

.titlebar .separator {
  color: if($variant == 'light', darken($header_bg, 7%), darken($header_bg, 5%));  //fixes separator in gnome-tweak-tool
}

GtkFileChooserDialog .dialog-action-box { background-color: $bg_color }  // fix for non gnome environments

NemoWindow GtkEventBox { background-color: $bg_color; } // fixes nemo statusbar

GtkFileChooserDialog *,
NautilusWindow *,
NemoWindow {
  -GtkPaned-handle-size: 0;
}

@if $variant==dark {
  GtkFileChooserDialog,
  NautilusWindow ,
  NemoWindow {
    .sidebar { box-shadow: inset -1px 0 $dark_sidebar_border; }

    .sidebar:dir(rtl) { box-shadow: inset 1px 0 $dark_sidebar_border; }
  }
}

// Dark transparent sidebars
GtkFileChooserDialog,
NautilusWindow,
NemoWindow,
MarlinViewWindow {

  &.csd.background,
  .source-list, .source-list.view, .source-list.view:prelight { background-color: transparent; }

  .sidebar, .source-list.sidebar.view {
    background-color: $dark_sidebar_bg;

    .view, row {
      background-color: transparent;
      color: $dark_sidebar_fg;

      &.image { color: transparentize($dark_sidebar_fg, 0.4); }

      &.cell:selected {
        background-color: $selected_bg_color;
        color: $selected_fg_color;
      }
    }

    &.frame {
      color: $dark_sidebar_fg;
    }

    .separator { color: transparent; }

    .scrollbar {

      &.overlay-indicator:not(.dragging):not(.hovering) .slider {
        background-color: lighten($dark_sidebar_fg, 15%);
        border: 1px solid transparentize(black, 0.7);
      }

      // trough coloring
      .trough {
        background-color: transparentize(black, 0.8);
        border: none;
      }

      // slider coloring
      .slider {
        background-color: transparentize(lighten($dark_sidebar_fg, 15%), 0.3);

        &:hover { background-color: lighten($dark_sidebar_fg, 20%); }

        &:prelight:active { background-color: $selected_bg_color; }

        &:insensitive {
          background-color: transparent;
        }
      }
    }
  }
  &.maximized .sidebar { background-color: opacify($dark_sidebar_bg, 1); }

  .pane-separator { background-color: $dark_sidebar_border; }
}

// Yeah, this is ugly, but prevents a transparent background in the image preview box
GtkFileChooserDialog GtkPaned > .vertical > .horizontal { background-color: $bg_color; }

// Gedit sidebar
GeditWindow.background.csd {
  background-color: transparent;

  .pane-separator,
  .pane-separator:hover { background-color: $dark_sidebar_border; }

  .titlebar .pane-separator { background-color: if($variant == 'light', darken($header_bg, 7%), darken($header_bg, 5%)); }

  .titlebar { background-color: transparent }

  .gedit-titlebar-left.titlebar,
  .gedit-titlebar-right.titlebar {
    background-color: $header_bg;

    &:backdrop { background-color: $header_bg_backdrop; }
  }
}

.gedit-bottom-panel-paned { background-color: $base_color; }

.gedit-document-panel {
  background-color: $dark_sidebar_bg;

  .maximized & { background-color: opacify($dark_sidebar_bg, 1); }

  .list-row { color: $dark_sidebar_fg; }

  .list-row {
    background-color: transparentize($dark_sidebar_fg, 1);
    border: solid transparentize($dark_sidebar_fg, 1);
    border-width: 3px 2px 3px 2px;
  }
  .list-row:hover {
    border: solid transparentize($dark_sidebar_fg, 0.85);
    border-width: 3px 2px 3px 2px;
    background-color: transparentize($dark_sidebar_fg, 0.85);
  }
  .list-row:active {
    color: $selected_fg_color;
    background-color: $selected_bg_color;
    border: solid $selected_bg_color;
    border-width: 3px 2px 3px 2px;

    .button { color: $selected_fg_color; }
  }
  .list-row:selected, .list-row:selected:hover {
    color: $selected_fg_color;
    background-color: $selected_bg_color;
    border: solid $selected_bg_color;
    border-width: 3px 2px 3px 2px;
  }
  .prelight-row .button:active {
    color: $dark_sidebar_fg;
  }
}

GeditWindow.background.csd GeditFileBrowserWidget {
  background-color: $dark_sidebar_bg;

  .maximized & { background-color: opacify($dark_sidebar_bg, 1); }

  .scrollbar {

    &.overlay-indicator:not(.dragging):not(.hovering) .slider {
      background-color: lighten($dark_sidebar_fg, 15%);
      border: 1px solid transparentize(black, 0.7);
    }

    // trough coloring
    .trough {
      background-color: transparentize(black, 0.8);
      border: none;
    }

    // slider coloring
    .slider {
      background-color: transparentize(lighten($dark_sidebar_fg, 15%), 0.3);

      &:hover { background-color: lighten($dark_sidebar_fg, 20%); }

      &:prelight:active { background-color: $selected_bg_color; }

      &:insensitive {
        background-color: transparent;
      }
    }
  }

  .horizontal {
    background-color: transparent;
    border-color: darken($dark_sidebar_bg, 7%);

    .button {
      @include button(undecorated);
      color: $dark_sidebar_fg;
      border: 1px solid transparent;

      &:hover { border: 1px solid $selected_bg_color; }
      &:active, &:checked { @include button(active); }
      &:insensitive { color: transparentize($dark_sidebar_fg, 0.6); }
    }
    GtkComboBox { color: $dark_sidebar_fg; }
  }
}

GeditWindow.background.csd GeditFileBrowserView.view {

  background-color: transparent;
  color: $dark_sidebar_fg;

  &.expander {
    color: $dark_sidebar_fg;
    &:hover { color: $selected_bg_color; }
  }
}

// Filechooser bottom bar
GtkFileChooserDialog .action-bar.frame {
  background-color: darken($dark_sidebar_bg, 2%);
  border-color: darken($dark_sidebar_bg, 7%);

  GtkLabel { color: $dark_sidebar_fg; }

  .button {
    @include button(undecorated);

    &:hover { border: 1px solid $selected_bg_color; }
    &:active, &:checked {
      border: 1px solid $selected_bg_color;
      color: $selected_fg_color;
      background-color: $selected_bg_color;
    }
    &:insensitive { color: transparentize($dark_sidebar_fg, 0.6); }
  }

  GtkComboBox { color: $dark_sidebar_fg; }
}