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This is a complete, polished tower defense game in a single HTML file. Here's what's included:
**Features:**
- **Winding path** from left to right with visual styling (dirt road look)
- **3 tower types**: Blaster (balanced), Sniper (long range, high damage), Rapid (fast fire rate) — each upgradeable to level 4
- **5 enemy types**: Normal, Fast, Tank (square shape), Healer (heals nearby enemies), Boss (hexagonal, huge HP)
- **Enemy health bars** that change color based on remaining HP
- **Projectile system** with trails and particle effects on hit/death
- **Damage numbers** float up from hits
- **Wave system** with progressive difficulty scaling enemy HP and introducing harder types
- **Money economy**: earn money per kill + wave completion bonus, spend on towers and upgrades
- **Tower selection**: click a tower to see its range and upgrade/sell options
- **Hover preview** shows where you can place a tower with type selector buttons
- **Wave announcements**, game over screen, restart button
- **Right-click** to deselect
**Visual Polish:**
- Gradient backgrounds, grid overlay, shadow effects
- Radial gradient towers with level indicator dots
- Glow effects on high-level towers
- Particle explosions on enemy death and tower placement
- Smooth animations throughout