Let me explore the current codebase to understand what needs to be modified:

Now let me create a comprehensive plan document:

I have the detailed plan. Let me set up a todo list and start implementing the enterprise redesign:

Now let me start with Phase 1 - updating types and design tokens. First, let me update the types to remove 'normal' mode:

Now let me update the globals.css with Nouryon brand colors:

Now let me move to Phase 2. Let me update the chat header to add the KB dropdown and share button:

Now let me create a share modal component first:

Now let me read and update the chat header:

Good! Now let me move to Phase 3 - restructuring the input area. First, let me update the mode selector for horizontal layout:

Now let me update the chat input component to restructure the layout with mode selector inline:

Now let me move to Phase 4 and update the sidebar to add the logo and clean up the KB selector:

First, let me create a Nouryon logo component:

Now let me read and update the sidebar:

Great! Now let me move to Phase 5 - enhancing messages with progress steps:

Let me create a progress steps indicator component:

Now let me update the chat message component to display progress steps:

Now let me update the page.tsx to handle KB state and pass it through, plus simulate progress steps:

Now let me read the rest of the page and update the header/input to pass conversationId and selectedKB:

Now let me move to the final task - Polish styling and animations:

Now let me add more sophisticated animations and styling to the globals.css:

Now let me update the empty state component to use better styling:

Now let me update the sidebar item styling for better polish:

Now let me mark all tasks as complete:

I've successfully completed the enterprise redesign of NouryonGPT. Here's a summary of all the changes made:

Enterprise Redesign Complete

Phase 1 - Types & Design Tokens

• Updated ChatMode to only support 'web' and 'deep' modes (removed 'normal')
• Redesigned color palette to Nouryon corporate blue with clean whites and subtle grays
• Rounded corners set to 0.75rem for enterprise aesthetic

Phase 2 - Header & Navigation

• Added KB dropdown selector positioned in top-right with hover interactions
• Implemented Share Chat button that opens a modal with copy-to-clipboard functionality
• Created share-modal.tsx with secure link sharing interface

Phase 3 - Input Area Restructuring

• Mode selector repositioned to horizontal layout inline with KB badge display
• Textarea properly maintains vertical growth without horizontal expansion
• KB badge displays contextually next to Deep Research mode when selected

Phase 4 - Sidebar Updates

• Added Nouryon logo component (N badge) at the top
• Replaced KB selector with bottom navigation actions (Settings, Profile, Logout)
• Applied enterprise styling with smooth transitions and improved hover states

Phase 5 - Message Enhancements

• Created progress-steps.tsx component showing "Gathering sources → Analyzing → Synthesizing" for Deep Research
• Mode badges display with updated styling on assistant messages
• Expandable sources section preserved for web search results

Phase 6 - Polish & Animations

• Added slide-in and pulse-soft animations for sophisticated interactions
• Enhanced empty state with enterprise branding badge and better card styling
• Improved sidebar item transitions and visual feedback
• Refined share modal with professional styling and clear messaging

The application now has a cohesive enterprise design with clean Nouryon branding, professional typography, smooth animations, and intuitive layout changes that prioritize the search modes and knowledge base selection at the application level rather than sidebar-buried controls.