fix backdrop overlay size

Author: micrum

README.md

@@ -17,6 +17,7 @@ Clone project:
 
 Install dependencies:
 
+    $ cd angular-material-dashboard
     $ npm install
 
 Install gem 'sass'

src/app/stylesheets/_custom.scss

@@ -136,6 +136,11 @@ md-radio-button.md-accent.md-checked .md-label span {
   font-size: $font-size-large;
 }
 
+
+md-backdrop.md-sidenav-backdrop {
+  position: fixed;
+}
+
 // libs overrides
 .material-icons {
   vertical-align: middle;