* Add the hero image.
* Remove code badges from the landing page
* Update the style of the mindmap
* Update the quote of knowledge sharing
* Fix a type
* Update the pull request template
* Update index.md of docs-en
* Update copyright
* Update the Python code
* Fix the code comments in ArrayBinaryTree
* Fix the code comments in ArrayBinaryTree
* Roll back time_comlexity.py
* Add the visualizing code(pythontutor) blocks to the chapter complexity, data structure, array and linked list, stack and queue, hash table, and backtracking
* Fix the code comments
* Update all the figures
* Update the data structure, sorting, divide and conquer chapters' covers. Add the English edition covers.
* Fix the link of EN translation in README
* Update README.md
* Update README.md
* Update README-en.md
* Update Dockerfile for code debugging.
* Format Python code using Black.
* Improve dark theme by defining html classes for the figures, animations and cover images.
* Fix several glossary translation.
* Update a code comment.
* Fix climbing_stairs_backtrack: the pruning should not require the sorted choices list.
* Update the code of array and list traversal.
* Fix a rendering issue of README.md
* Update code of list traversal.
* Fix array_definition.png
* Update README.md
* Fix max_capacity_moving_short_board.png
* Fix array.dart
* Fix array.dart
* Fix array.dart
* Fix array.dart