Fix mobile background

diff --git a/css/style.css b/css/style.css
index 300b3a5..74292f9 100644
--- a/css/style.css
+++ b/css/style.css
@@ -10,7 +10,10 @@
   -moz-background-size: cover;
   -o-background-size: cover;
   background-size: cover;
-  
+  /* Preserve aspet ratio */
+  min-width: 100%;
+  min-height: 100%;
+  background-attachment: fixed;
   }
 
 #bg {