Added theme for button

I18N Commander/App/scenes/BtnIcon.tscn

@@ -1,22 +1,16 @@
-[gd_scene load_steps=2 format=3 uid="uid://d0x0yv7nevod7"]
+[gd_scene load_steps=3 format=3 uid="uid://d0x0yv7nevod7"]
 
 [ext_resource type="Script" path="res://scenes/BtnIcon.cs" id="1_b787p"]
+[ext_resource type="Theme" uid="uid://uqhultm05f5a" path="res://theme/ui_theme.tres" id="2_8n123"]
 
-[node name="btn_icon" type="Control"]
-layout_mode = 3
-anchors_preset = 15
-anchor_right = 1.0
-anchor_bottom = 1.0
-grow_horizontal = 2
-grow_vertical = 2
+[node name="btn_icon" type="MarginContainer"]
+theme_override_constants/margin_left = 6
+theme_override_constants/margin_top = 6
+theme_override_constants/margin_right = 6
+theme_override_constants/margin_bottom = 6
 script = ExtResource("1_b787p")
 
-[node name="margin" type="MarginContainer" parent="."]
-layout_mode = 0
-offset_right = 40.0
-offset_bottom = 40.0
-
-[node name="btn" type="Button" parent="margin"]
+[node name="btn" type="Button" parent="."]
 unique_name_in_owner = true
 layout_mode = 2
-theme_override_constants/h_separation = 6
+theme = ExtResource("2_8n123")