Functional requirements Text translation function Input field for text with a volume of 1-400 characters Translation is displayed in the right field after 1 second of user inactivity Translation into English should accurately convey the meaning of the original text Language detection system When entering text in Russian, the system automatically: • Detects the source language as Russian • Sets the translation language to English When entering text in English, the system automatically: • Detects the source language as English • Sets the translation language to Russian Managing the word collection Adding to the collection: Button "Add to collection" is available next to the translated text On click, a confirmation appears: "Translation added to the 'Favorites' collection" The element appears in the "Collection" tab Removing from the collection: Button "Remove from collection" is available for each item in the collection On click, a confirmation appears: "Removed from 'Favorites'" The element is immediately removed from the collection Document translation Supported formats: DOCX documents in Russian Upload process: Navigate to the "Documents" tab Select a file via the "Choose manually" element Processing time: up to 2 minutes Translation result: Status "Document translation completed" Active button "Download translation" Download the file with the original name The file content contains a correct translation into English

To implement the described system, the following functional blocks must be provided:

1. Text translation function:

• Input field with a length limit of 1-400 characters.
• User inactivity tracking (1-second timer) to trigger translation.
• Translate text while preserving meaning (use a quality translator, e.g., Google Translate API or a custom model).

2. Language detection:

• Automatically detect the language (Russian or English) when text is entered.
• Set the translation language depending on the source language (Russian → English, English → Russian).
• Language detection can be implemented using libraries such as langdetect.

3. Word collection management:

• "Add to collection" button next to the translation.
• Show confirmation upon adding and save the item in the "Collection" tab.
• In the "Collection" tab, each item has a "Remove from collection" button with confirmation and immediate removal.

4. Document translation:

• Support uploading DOCX files in Russian.
• Interface for selecting files in the "Documents" tab.
• Process the file (up to 2 minutes) with content translation.
• After completion, display the status "Document translation completed" and an active "Download translation" button.
• The downloadable file should retain the original name and contain a correct English translation.

For testing:

• Verify translation accuracy with different input languages.
• Check the inactivity timer functionality.
• Verify adding and removing items from the collection with confirmation displays.
• Test uploading, processing, and downloading translated documents.

This approach will ensure compliance with functional requirements and user convenience.