Update CSS collections

collections/css/background-patterns.yaml

@@ -0,0 +1,14 @@
+slug: css/background-patterns
+name: CSS Background Patterns
+featured: true
+snippetIds:
+  - css/s/stripes-pattern
+  - css/s/zig-zag-pattern
+  - css/s/polka-dot-pattern
+  - css/s/checkerboard-pattern
+splash: tea-pour.png
+description: >-
+  CSS can be used to create a variety of background patterns. In this
+  collection, you'll learn how to create a few simple background patterns, such
+  as stripes, zig-zags, polka dots, and checkerboards.
+shortDescription: Learn how to create a variety of background patterns using CSS.