niri: Add dynamic screencasting keybinds

tree/.config/niri/config.kdl.tpl

@@ -253,6 +253,29 @@ window-rule {
     clip-to-geometry true
 }
 
+// Indicate screencasted windows with red colors.
+window-rule {
+    match is-window-cast-target=true
+
+    focus-ring {
+        active-color "#f38ba8"
+        inactive-color "#7d0d2d"
+    }
+
+    border {
+        inactive-color "#7d0d2d"
+    }
+
+    shadow {
+        color "#7d0d2d70"
+    }
+
+    tab-indicator {
+        active-color "#f38ba8"
+        inactive-color "#7d0d2d"
+    }
+}
+
 window-rule {
     match title="Volume Indicator"
     geometry-corner-radius 35
@@ -497,6 +520,11 @@ binds {
     // moving the mouse or pressing any other key.
     // Mod+Shift+P { power-off-monitors; }
 
+    // Dynamic screencasting target
+    Mod+Slash { clear-dynamic-cast-target; }
+    Mod+Ctrl+Slash { set-dynamic-cast-window; }
+    Mod+Shift+Slash { set-dynamic-cast-monitor; }
+
     // Debugging
     Mod+Shift+Ctrl+T { toggle-debug-tint; }
     Mod+Shift+Ctrl+O { debug-toggle-opaque-regions; }