diff --git a/orx-panel/src/demo/kotlin/DemoHorizontalLayout01.kt b/orx-panel/src/demo/kotlin/DemoHorizontalLayout01.kt
index 351675f3..9de6945d 100644
--- a/orx-panel/src/demo/kotlin/DemoHorizontalLayout01.kt
+++ b/orx-panel/src/demo/kotlin/DemoHorizontalLayout01.kt
@@ -27,6 +27,7 @@ fun main() = application {
                 // ----------------------------------------------
                 display = Display.FLEX
                 flexDirection = FlexDirection.Row
+                width = 100.percent
             }
 
             styleSheet(has type "h1") {