widgets: flat style for dropdown and spinbutton

src/main.py

@@ -23,7 +23,7 @@ import gi
 gi.require_version('Gtk', '4.0')
 gi.require_version('Adw', '1')
 
-from gi.repository import Gtk, Gio, Adw
+from gi.repository import Gtk, Gio, Adw, Gdk
 from .window import TuneitWindow
 from .about import build_about_dialog
 
@@ -44,6 +44,12 @@ class TuneitApplication(Adw.Application):
         self.create_action('about', self.on_about_action)
         self.create_action('preferences', self.on_preferences_action)
 
+        css = Gtk.CssProvider()
+        css.load_from_resource('/ru.ximperlinux.TuneIt/style.css')
+        Gtk.StyleContext.add_provider_for_display(
+            Gdk.Display.get_default(), css, Gtk.STYLE_PROVIDER_PRIORITY_APPLICATION
+        )
+
         _application = self
 
     def do_activate(self):

src/settings/setting/widgets/ChoiceWidget.py

@@ -10,6 +10,9 @@ class ChoiceWidget(BaseWidget):
         self.dropdown = Gtk.DropDown.new(self.model, expression)
         self.dropdown.set_halign(Gtk.Align.CENTER)
         self.dropdown.set_valign(Gtk.Align.CENTER)
+        btn = self.dropdown.get_first_child()
+        btn.add_css_class("flat")
+        btn.add_css_class("dropdown-flat")
 
         self.handler_id = self.dropdown.connect("notify::selected", self._on_choice_changed)
 

src/settings/setting/widgets/NumStepper.py

@@ -17,6 +17,7 @@ class NumStepper(BaseWidget):
         self.spin = Gtk.SpinButton(
             valign=Gtk.Align.CENTER,
             halign=Gtk.Align.CENTER,
+            css_classes=["flat"],
         )
 
         lower, upper, step, digits = self._get_range_values(map_data)

src/style.css

+.dropdown-flat {
+    font-weight: normal;
+    padding: 0 2px;
+}
+
+.dropdown-flat:hover,
+.dropdown-flat:active,
+.dropdown-flat:checked {
+    background: none;
+}

src/tuneit.gresource.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <gresources>
   <gresource prefix="/ru.ximperlinux.TuneIt">
+    <file>style.css</file>
     <file preprocess="xml-stripblanks">window.ui</file>
     <file preprocess="xml-stripblanks">settings/widgets/panel_row.ui</file>
     <file preprocess="xml-stripblanks">settings/widgets/deps_alert_dialog.ui</file>