3D cartoon parking lot slide puzzle game with city bus theme. Drag colored buses and cars horizontally or vertically to clear a straight driving path for the target orange bus, drive the bus into the marked parking exit "P" to finish each level, collect up to 3 star ratings based on operation efficiency.

Core Slide & Escape Rules:
1. Vehicle Slide Physics: Every vehicle can only move along its facing direction (horizontal cars slide left/right, vertical cars slide up/down). Cars stop moving once hitting another vehicle or the parking lot boundary wall.
2. Escape Win Condition: Fully clear an unobstructed straight passage from the orange target bus to the exit marked with "P" sign, then drag the orange bus all the way to the exit zone to complete the level.
3. Star Rating Mechanic: Fewer total slide moves = higher star reward. Complete the stage with minimal steps to unlock full 3 stars.
4. Hidden Special Mechanic: Special hidden door event unlocks randomly every 5 cleared levels, adding extra bonus rewards and hidden challenge stages.

Progressive Level Difficulty Design:
- Level Select Interface: Grid layout stage buttons. Level 1/2/3 unlocked at new game start; all subsequent levels locked with padlock icons. Each cleared level displays its earned star rating below the stage number.
- Early Beginner Stages (Lv.1~3): Sparse vehicle layout, wide blank space on the parking lot. Only a small number of gray ordinary cars block the orange bus’s exit path, simple single-layer blocking logic for new players to learn slide rules.
- Mid Game Stages (Lv.5+): Dense multi-layer vehicle stacking, mixed horizontal & vertical cars cross-blocking the escape route. Players need to move multiple groups of cars in sequence to create a continuous straight channel, plus random hidden door bonus events every 5 levels.
- Advanced Hard Stages: Fully packed parking lot grid, multi-direction cross blocking, long winding escape paths that require precise step planning to earn 3-star perfect ratings.

Complete Game UI Layout:
1. Level Selection Screen
- Top Left: Home house return icon
- Top Center: Big "LEVELS" stage menu title
- Background: City roadside parking lot illustration with silver bus, traffic cones, blue sky & cloud cartoon backdrop
- Stage Grid: Light blue rounded stage number buttons, cleared levels show star score underneath; uncleared levels covered with dark lock padlock
- Bottom: Page left/right scroll navigation arrows

2. In-Game Puzzle Screen
- Top Bar:
Left: "LEVEL X" current stage label
Middle: 3-star rating preview panel
Right: Gift reward box button + pause gameplay button
- Central Play Area: Top-down 2D parking lot grid map, gray regular cars, red/orange target buses, blue small trucks, exit marked with white "P" parking sign
- Tip Text Popup: "A door is randomly hidden every 5 levels." reminds players of periodic bonus hidden door content

3. Level Complete Victory Screen
- Central Panel: Retro TV-style result frame, shows earned star rating + completed level number
- Bottom Functional Buttons (left to right):
Level list menu button, replay current level button, unlock next level forward arrow button

Visual Art Style:
Bright 3D cartoon rendering style, clean gray asphalt parking ground, colorful cartoon vehicles, soft gradient sky background with cloud rays, simple traffic cone & city building decorations, kid-friendly bright low-stimulation color palette suitable for all ages.

Relaxing brain teaser parking puzzle: intuitive drag slide controls, progressive crowded parking lot layouts, 3-star perfect score challenge and random hidden bonus door rewards, train your spatial planning and forward reasoning ability while moving buses to escape the lot!