diff --git a/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/04.use-of-basic-optical-elements/01.plane-refracting-surface/07.plane-refracting-surface-level-up/portal.en.md b/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/04.use-of-basic-optical-elements/01.plane-refracting-surface/07.plane-refracting-surface-level-up/portal.en.md
index f4c5db0b0..e002b772f 100644
--- a/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/04.use-of-basic-optical-elements/01.plane-refracting-surface/07.plane-refracting-surface-level-up/portal.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/04.use-of-basic-optical-elements/01.plane-refracting-surface/07.plane-refracting-surface-level-up/portal.en.md
@@ -1,5 +1,7 @@
 ---
 title: 'Refraction matrix (next level)'
+published: false
+visible: false
 hero_classes: ''
 hero_image: ''
 ---