"Raised, the bridge stands a proud 90° to the ground. Cranked, it falls… but old gears always jam. And the toll? The toll is the difference."
You are the bridge manager of Bluewater Keep. Travelers arrive at the moat and call for the bridge. Spin the crank wheel (drag it round!) or mash the crank button — but the rusty gears always jam partway (that drop is angle b).
Then tell the gears exactly how many more degrees to drop (angle a). Wrong numbers leave the bridge hanging — and travelers shouting! Finally charge the toll: first drop − extra drop, in gold.
Crank: spin the wheel by the toll master, tap the button, or press Space/E · Numbers: −/+ or ↑↓, Enter confirms · 📜 on the wall shows the real exam question
📜 The Real Exam Question
This bridge was built from an actual exam problem — the numbers change with each traveler.
Solve it on paper, then run the bridge and see it come alive.
🏆 Toll master of Bluewater Keep!
"Three travelers crossed, three tolls fairly counted. The kingdom's geometry is safe in your hands."
Every bridge: it stands at 90°. Drop b, and what remains is a = 90 − b. The toll is the difference: b − a.