frontend_design.txt

The frontend will be a single HTML page with embedded JavaScript and CSS. It will have the following components:

1. HTML Structure:
   - Header with app title
   - Form for adding/editing expenses
   - Table to display expenses
   - Charts section for visualizing spending
   - Categories management section

2. CSS Styling:
   - Use a modern, responsive design
   - Implement a clean, minimalist color scheme
   - Use Flexbox or Grid for layout

3. JavaScript Functionality:
   - Fetch and display expenses from the backend
   - Handle form submission for adding/editing expenses
   - Implement client-side form validation
   - Create interactive charts using Chart.js library
   - Enable sorting and filtering of the expense table
   - Implement category management (add, edit, delete)

4. Charts and Visualizations:
   - Pie chart for expenses by category
   - Bar chart for monthly spending
   - Line chart for spending trends over time

5. Interactive Elements:
   - Clickable table rows to edit expenses
   - Toggle between one-time and recurring expenses view
   - Date range picker for filtering expenses

6. Responsive Design:
   - Ensure the layout adapts to different screen sizes
   - Use media queries to adjust the layout for mobile devices

7. Dependencies:
   - Chart.js for creating interactive charts
   - Axios for making API requests
   - Date-fns for date manipulation

The frontend will provide an intuitive interface for users to manage their expenses, visualize spending patterns, and gain insights into their financial habits.