diff --git a/static/css/01-foundation/_themes.css b/static/css/01-foundation/_themes.css
index fc9ddc1..bbab290 100644
--- a/static/css/01-foundation/_themes.css
+++ b/static/css/01-foundation/_themes.css
@@ -77,9 +77,11 @@
   /* Page Background - Medium gray for dark pattern visibility */
   --page-bg: #3a3a3a;
 
-  /* Diagonal Grid with Green Glow - Dark */
-  --page-bg-pattern: repeating-linear-gradient(45deg, rgba(0, 255, 128, 0.15) 0, rgba(0, 255, 128, 0.15) 1px, transparent 1px, transparent 20px),
-                     repeating-linear-gradient(-45deg, rgba(0, 255, 128, 0.15) 0, rgba(0, 255, 128, 0.15) 1px, transparent 1px, transparent 20px);
+  /* Concentric Squares Pattern - Dark (same shape as light, adapted colors) */
+  --page-bg-pattern: repeating-linear-gradient(0deg, transparent, transparent 5px, rgba(200, 210, 220, 0.06) 5px, rgba(200, 210, 220, 0.06) 6px, transparent 6px, transparent 15px),
+                     repeating-linear-gradient(90deg, transparent, transparent 5px, rgba(200, 210, 220, 0.06) 5px, rgba(200, 210, 220, 0.06) 6px, transparent 6px, transparent 15px),
+                     repeating-linear-gradient(0deg, transparent, transparent 10px, rgba(180, 190, 200, 0.04) 10px, rgba(180, 190, 200, 0.04) 11px, transparent 11px, transparent 30px),
+                     repeating-linear-gradient(90deg, transparent, transparent 10px, rgba(180, 190, 200, 0.04) 10px, rgba(180, 190, 200, 0.04) 11px, transparent 11px, transparent 30px);
 
   /* Paper/Card Backgrounds */
   --paper-bg: #1a1a1a;
@@ -135,9 +137,11 @@
     /* Page Background - Medium gray for dark pattern visibility */
     --page-bg: #3a3a3a;
 
-    /* Diagonal Grid with Green Glow - Dark */
-    --page-bg-pattern: repeating-linear-gradient(45deg, rgba(0, 255, 128, 0.15) 0, rgba(0, 255, 128, 0.15) 1px, transparent 1px, transparent 20px),
-                       repeating-linear-gradient(-45deg, rgba(0, 255, 128, 0.15) 0, rgba(0, 255, 128, 0.15) 1px, transparent 1px, transparent 20px);
+    /* Concentric Squares Pattern - Dark (same shape as light, adapted colors) */
+    --page-bg-pattern: repeating-linear-gradient(0deg, transparent, transparent 5px, rgba(200, 210, 220, 0.06) 5px, rgba(200, 210, 220, 0.06) 6px, transparent 6px, transparent 15px),
+                       repeating-linear-gradient(90deg, transparent, transparent 5px, rgba(200, 210, 220, 0.06) 5px, rgba(200, 210, 220, 0.06) 6px, transparent 6px, transparent 15px),
+                       repeating-linear-gradient(0deg, transparent, transparent 10px, rgba(180, 190, 200, 0.04) 10px, rgba(180, 190, 200, 0.04) 11px, transparent 11px, transparent 30px),
+                       repeating-linear-gradient(90deg, transparent, transparent 10px, rgba(180, 190, 200, 0.04) 10px, rgba(180, 190, 200, 0.04) 11px, transparent 11px, transparent 30px);
 
     /* Paper/Card Backgrounds */
     --paper-bg: #1a1a1a;
diff --git a/static/css/04-interactive/_chat.css b/static/css/04-interactive/_chat.css
index 4782732..753efd7 100644
--- a/static/css/04-interactive/_chat.css
+++ b/static/css/04-interactive/_chat.css
@@ -358,7 +358,7 @@
 .chat-avatar-juan {
     width: 36px;
     height: 36px;
-    background: none;
+    background: #ffffff;
     padding: 0;
     overflow: hidden;
 }