Doc imp (#13148)

* added intro, item and prices video, fixed image links in item and prices

* update 2: first 5 videos added

* added all videos to the user manual

* updated .gitignore
diff --git a/erpnext/docs/assets/css/docs-erp.css b/erpnext/docs/assets/css/docs-erp.css
new file mode 100644
index 0000000..5ac7516
--- /dev/null
+++ b/erpnext/docs/assets/css/docs-erp.css
@@ -0,0 +1,14 @@
+.embed-container { 
+    position: relative; 
+    padding-bottom: 56.25%; 
+    height: 0; 
+    overflow: hidden; 
+    max-width: 100%; } 
+    
+.embed-container iframe, .embed-container object, .embed-container embed { 
+    position: absolute; 
+    top: 0; 
+    left: 0; 
+    width: 100%; 
+    height: 100%; 
+}
\ No newline at end of file