diff --git a/crates/oa-desktop/src/behavior.rs b/crates/oa-desktop/src/behavior.rs
index 0a0c4df4..0a5b9d95 100644
--- a/crates/oa-desktop/src/behavior.rs
+++ b/crates/oa-desktop/src/behavior.rs
@@ -2074,7 +2074,7 @@ impl canvas::Program<Message> for Scene {
                     .with_color(if activation.call == self.selected {
                         style::TEAL
                     } else {
-                        style::LINE
+                        style::BOUNDARY
                     })
                     .with_width(if activation.call == self.selected {
                         2.5
@@ -2091,7 +2091,7 @@ impl canvas::Program<Message> for Scene {
             let color = if b.id == self.selected {
                 style::TEAL
             } else {
-                style::LINE
+                style::BOUNDARY
             };
             if outline {
                 f.stroke(
diff --git a/crates/oa-desktop/src/behavior/scenario_lifecycle/render.rs b/crates/oa-desktop/src/behavior/scenario_lifecycle/render.rs
index 989fb2d5..e12b3cf9 100644
--- a/crates/oa-desktop/src/behavior/scenario_lifecycle/render.rs
+++ b/crates/oa-desktop/src/behavior/scenario_lifecycle/render.rs
@@ -240,9 +240,9 @@ impl Rendering {
                     ..Stroke::default()
                         .with_width(1.)
                         .with_color(if id == selected {
-                            Color::from_rgb8(148, 190, 187)
+                            style::TEAL
                         } else {
-                            Color::from_rgb8(214, 222, 222)
+                            style::BOUNDARY
                         })
                 },
             );
@@ -262,7 +262,7 @@ impl Rendering {
                             if lifetime.lifeline == selected {
                                 style::TEAL
                             } else {
-                                Color::from_rgb8(91, 113, 113)
+                                style::BOUNDARY
                             },
                         ),
                     ),
diff --git a/crates/oa-desktop/src/behavior/state_canvas.rs b/crates/oa-desktop/src/behavior/state_canvas.rs
index 883a736a..52afffaa 100644
--- a/crates/oa-desktop/src/behavior/state_canvas.rs
+++ b/crates/oa-desktop/src/behavior/state_canvas.rs
@@ -1514,7 +1514,7 @@ fn paint_node(
     }
     for (relation, row) in state_action_rows(project, node) {
         if relation.id == selected {
-            frame.fill_rectangle(row.position(), row.size(), Color::from_rgb8(224, 247, 242));
+            paint_selected_row(frame, row);
         }
         label_text(
             frame,
@@ -1530,7 +1530,7 @@ fn paint_node(
     }
     for (relation, row) in internal_rows(project, node) {
         if relation.id == selected {
-            frame.fill_rectangle(row.position(), row.size(), Color::from_rgb8(224, 247, 242));
+            paint_selected_row(frame, row);
         }
         frame.stroke(
             &line(row.position(), Point::new(row.x + row.width, row.y)),
@@ -1565,6 +1565,22 @@ fn paint_node(
     }
 }
 
+fn paint_selected_row(frame: &mut Frame, row: Rectangle) {
+    frame.fill_rectangle(row.position(), row.size(), Color::from_rgb8(224, 247, 242));
+    if row.width <= 2. || row.height <= 2. {
+        return;
+    }
+    // Selection remains visible without hue. Keep the outline inside the
+    // existing row so it cannot cover its separator or change its hit bounds.
+    frame.stroke(
+        &Path::rectangle(
+            row.position() + Vector::new(1., 1.),
+            Size::new(row.width - 2., row.height - 2.),
+        ),
+        Stroke::default().with_color(style::TEAL).with_width(1.5),
+    );
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/crates/oa-desktop/src/diagram.rs b/crates/oa-desktop/src/diagram.rs
index 8008704f..a53a1650 100644
--- a/crates/oa-desktop/src/diagram.rs
+++ b/crates/oa-desktop/src/diagram.rs
@@ -1173,7 +1173,7 @@ impl canvas::Program<Message> for DiagramCanvas<'_> {
             } else if edge.trace {
                 Color::from_rgb8(134, 107, 168)
             } else {
-                Color::from_rgb8(144, 158, 173)
+                style::BOUNDARY
             };
             let capability_label = relationship_stereotype(project, edge.id);
             let mut stroke =
@@ -1596,7 +1596,11 @@ fn paint_node(f: &mut Frame, p: &Project, n: &ProjectedNode, selected: Id, conta
     };
     f.fill(&path, if container { tint } else { Color::WHITE });
     let mut stroke = Stroke::default()
-        .with_color(if e.id == selected { color } else { style::LINE })
+        .with_color(if e.id == selected {
+            color
+        } else {
+            style::BOUNDARY
+        })
         .with_width(if e.id == selected { 2.6 } else { 1.2 });
     if n.allocation_summary {
         stroke.line_dash = canvas::LineDash {