Custom components for Polymer Project (polymer-project.org). This modifies the existing core drawer panel to have a middle responsive step.
To view this component in action you can go here. Which is a working example that combines the drawer with my header wrapper to give you a general site layout.
You can also view the demo directly by going here.
This project can also be installed using bower just like polymer. It should download all needed files. bower install tikicoder/trutek-tri-drawer-panel