A clean, modern graphical user interface (GUI) template, designed for desktop applications. The layout includes a top navigation bar with icons and a title, a collapsible sidebar menu on the left with neatly labeled buttons, and a main content area with cards, input fields, and buttons. Use a light color scheme with subtle shadows and smooth gradients. Typography should be minimal and professional. Include elements like dropdown menus, toggles, tabs, and notification icons. The design should follow material design or flat design principles, optimized for UX/UI presentations.