diff --git a/dotfiles/gtk4.css b/dotfiles/gtk4.css
new file mode 100644
index 0000000..facce24
--- /dev/null
+++ b/dotfiles/gtk4.css
@@ -0,0 +1,3 @@
+tooltip, menu, window, frame, popover > contents {
+  border-radius: 0;
+}
diff --git a/dotfiles/xsession b/dotfiles/xsession
index e4f15e6..65963e7 100755
--- a/dotfiles/xsession
+++ b/dotfiles/xsession
@@ -45,6 +45,7 @@ Xresources   .Xresources
 XCompose     .XCompose
 gtkrc-2.0    .gtkrc-2.0
 gtk3.css     .config/gtk-3.0/gtk.css
+gtk3.css     .config/gtk-4.0/gtk.css
 qt5ct.conf   .config/qt5ct/qt5ct.conf
 qt5ct.conf   .config/qt6ct/qt6ct.conf
 systemd      .config/systemd/user