fix: replace profile cycle button with ComboBox for instant style switching

src/reader.rs

@@ -26,7 +26,7 @@ pub struct ReaderAction {
     pub toggle_theme: bool,
     pub toggle_bookmark: bool,
     pub toggle_kraft_bg: bool,
-    pub cycle_profile: bool,
+    pub switch_to_profile: Option<String>,
     pub page_next: bool,
     pub page_prev: bool,
 }
@@ -42,13 +42,14 @@ pub fn reading_view(
     _file_path: &str,
     kraft_texture: Option<&egui::TextureHandle>,
     use_kraft_bg: bool,
+    profile_names: &[String],
 ) -> ReaderAction {
     let mut action = ReaderAction {
         go_back: false,
         toggle_theme: false,
         toggle_bookmark: false,
         toggle_kraft_bg: false,
-        cycle_profile: false,
+        switch_to_profile: None,
         page_next: false,
         page_prev: false,
     };
@@ -98,12 +99,17 @@ pub fn reading_view(
                     if ui.button("A⁺").on_hover_text("放大字体").clicked() {
                         style.font_size = (style.font_size + 2.0).min(48.0);
                     }
-                    if ui.button(&style.name)
-                        .on_hover_text(format!("样式: {} (点击切换)", style.name))
-                        .clicked()
-                    {
-                        action.cycle_profile = true;
-                    }
+                    egui::ComboBox::from_id_salt("profile_selector")
+                        .width(110.0)
+                        .selected_text(&style.name)
+                        .show_ui(ui, |ui| {
+                            for name in profile_names {
+                                let selected = *name == style.name;
+                                if ui.selectable_label(selected, name).clicked() {
+                                    action.switch_to_profile = Some(name.clone());
+                                }
+                            }
+                        });
                     let kraft_icon = if use_kraft_bg { "📄" } else { "📋" };
                     if ui.button(kraft_icon).on_hover_text("牛皮纸背景").clicked() {
                         action.toggle_kraft_bg = true;