Responsive Web Design for a Brokerage Management System

We are looking to get a responsive UI designed for a brokerage management system. There are screens to be created for landing page, user management, user profiles, transaction management, document management etc. We will provide more details to selected freelancers. The UI designed must be responsive and work across devices seamlessly. The UI should be easily integrated to a PHP/MySQL backend and should be configurable for different clients in a multi-tenant environment. You may use professional colors/fonts to begin with and we should be able to change them later on if required by changing the CSS. Please provide some samples of your past work. Thanks, Automyze Consulting