Create a large glass aquarium whose side panel develops a visible crack and then bursts. The simulation must include: - Water escaping through the opening with flow strength based on water depth and decreasing as the tank drains - A curved water jet affected by gravity - A spreading puddle that collides with the room boundaries - Fish, rocks, plants, and a floating toy reacting differently according to density, buoyancy, drag, and current - Objects transitioning correctly from underwater motion to airborne motion and then to floor collisions - Fish attempting to swim against the current before being swept through the breach - Glass fragments with angular velocity, collisions, and water resistance - A visible waterline that lowers continuously rather than disappearing all at once Let the user drag the crack vertically before triggering the failure. A lower crack should initially produce a stronger jet than a higher crack. Give me 1 html file

**Modifying index.html**

I need to make some changes to the index.html file located in /tmp/ws. It seems like I should build it afterward to see if everything works properly. I wonder if I should check if it's empty first, though. It’s always good to inspect the file before proceeding, just to ensure there’s something to work with. Let’s get that sorted!

**Building a one-file app**

I need to create a rich one-file app, and I must ensure it meets the requirements. I plan to use inline HTML, CSS, and JavaScript without any external resources. Visual polish is essential, so I'll incorporate controls for dragging and cracking, as well as buttons. I want to implement physics simulation with canvas, including particles, object physics, fragments, and water boundaries. Testing for file existence is likely necessary, but I’ll focus on crafting a substantial app first.