diff --git a/content/u/advent-calendar/03/contents.lr b/content/u/advent-calendar/03/contents.lr
index 88b6305..1747e91 100644
--- a/content/u/advent-calendar/03/contents.lr
+++ b/content/u/advent-calendar/03/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-3.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 03:
 ---
 headline2: 20% off 
diff --git a/content/u/advent-calendar/04/contents.lr b/content/u/advent-calendar/04/contents.lr
index b196835..1943ba3 100644
--- a/content/u/advent-calendar/04/contents.lr
+++ b/content/u/advent-calendar/04/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: u/image/cards/advent-4.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 04:
 ---
 headline2: 20% off 
diff --git a/content/u/advent-calendar/05/contents.lr b/content/u/advent-calendar/05/contents.lr
index 32bc6ae..99e5d91 100644
--- a/content/u/advent-calendar/05/contents.lr
+++ b/content/u/advent-calendar/05/contents.lr
@@ -10,6 +10,12 @@ subtitle:
 ---
 image: /u/image/cards/advent-5.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 5:
 ---
 headline2: 20% off
diff --git a/content/u/advent-calendar/06/contents.lr b/content/u/advent-calendar/06/contents.lr
index 413d0af..3a3967f 100644
--- a/content/u/advent-calendar/06/contents.lr
+++ b/content/u/advent-calendar/06/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-6.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 6:
 ---
 headline2: 20% off 
diff --git a/content/u/advent-calendar/07/contents.lr b/content/u/advent-calendar/07/contents.lr
index c0c6e76..4bbf7a1 100644
--- a/content/u/advent-calendar/07/contents.lr
+++ b/content/u/advent-calendar/07/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-7.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 7:
 ---
 headline2: 20% off
diff --git a/content/u/advent-calendar/10/contents.lr b/content/u/advent-calendar/10/contents.lr
index 8e80773..c38231b 100644
--- a/content/u/advent-calendar/10/contents.lr
+++ b/content/u/advent-calendar/10/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-10.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 10:
 --- 
 headline2: 20% off 
diff --git a/content/u/advent-calendar/11/contents.lr b/content/u/advent-calendar/11/contents.lr
index a4f5458..f9835e6 100644
--- a/content/u/advent-calendar/11/contents.lr
+++ b/content/u/advent-calendar/11/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-11.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 11:
 ---
 headline2: 20% off
diff --git a/content/u/advent-calendar/12/contents.lr b/content/u/advent-calendar/12/contents.lr
index a54b305..e53a748 100644
--- a/content/u/advent-calendar/12/contents.lr
+++ b/content/u/advent-calendar/12/contents.lr
@@ -10,6 +10,12 @@ subtitle: 20% off for 10 limited VMs
 ---
 image: /u/image/cards/advent-12.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 12:
 --- 
 headline2: 20% off
diff --git a/content/u/advent-calendar/13/contents.lr b/content/u/advent-calendar/13/contents.lr
index 8ac2485..33d90f9 100644
--- a/content/u/advent-calendar/13/contents.lr
+++ b/content/u/advent-calendar/13/contents.lr
@@ -10,6 +10,12 @@ subtitle:
 ---
 image: /u/image/cards/advent-13.jpg
 ---
+header_background_color: #C12107
+---
+header_text_color: text-light
+---
+nav_classes: navbar-dark
+---
 headline1: Surprise 13:
 ---
 headline2: 20% off