[gnome-contacts] ContactSheet: use flat style for buttons

[Niels De Graef <nielsdg src gnome org>]

commit c3e8712f3287ec5c9411559722faa18a8779df77
Author: Julian Sparber <julian sparber net>
Date:   Mon Jul 1 17:05:48 2019 +0200

    ContactSheet: use flat style for buttons

 data/ui/style.css               | 9 +++++++++
 src/contacts-contact-sheet.vala | 1 +
 2 files changed, 10 insertions(+)
---
diff --git a/data/ui/style.css b/data/ui/style.css
index d77b446..763703c 100644
--- a/data/ui/style.css
+++ b/data/ui/style.css
@@ -60,3 +60,12 @@ row.contact-data-row {
   border-radius: 50%;
   padding: 0 0;
 }
+
+.contacts-flatten:not(:hover) {
+  background-color: transparent;
+  background-image: none;
+  border-color: transparent;
+  box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0);
+  text-shadow: none; -gtk-icon-shadow: none;
+  border: 1px solid rgba(205, 199, 194, 0.5);
+}
diff --git a/src/contacts-contact-sheet.vala b/src/contacts-contact-sheet.vala
index 17ebb6c..2315a97 100644
--- a/src/contacts-contact-sheet.vala
+++ b/src/contacts-contact-sheet.vala
@@ -39,6 +39,7 @@ public class Contacts.ContactSheet : ContactForm {
   private Button create_button (string icon) {
     var button = new Button.from_icon_name (icon, IconSize.BUTTON);
     button.set_halign (Align.END);
+    button.get_style_context ().add_class ("contacts-flatten");
 
     return button;
   }