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Design
The overall design of our interface (as shown in screenshots below) was meant to be a clean, simple application for an enterprise audience. We spent a great deal of time researching enterprise design patterns, and found that using grays and one highlighting color (red in our case) made for a professional looking application. High level navigation between interfaces was done using a horizontal tab system, familiar to many corporate sites. Each tab is generally self-contained in terms of functionality, however the underlying database on trips is shared across tabs. As the user navigated, we wanted to maintain state in each tab independently because some users may be using multiple interfaces at once (i.e. a manager who is approving trips for subordinates while planning a trip themselves).
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