TITLE: LINE 7 — TRANSIT
PROMPT: Create 'LINE 7 — TRANSIT', a living transit-map experience. Bold colored route lines with rounded 45° bends (SVG), interchange rings, and terminals; a train dot travels the polyline continuously with easing between stations, announcing each in a flip-board-style readout; schematic city landmarks at key stops. Palette: bone background, classic transit hues (red, emerald, amber, azure). Interactions: clicking any station recenters and opens a small tiled card (stop name, zone, first/last); a trip planner lets you pick origin/destination and animates the fastest route highlight with an ETA; speed control retimes the whole line; night mode dims to dark board. Orderly, kinetic, public-transport joy.
DESCRIPTION: A bone-paper transit board with hard offset shadows and a bold red Line 7 drawn as an SVG polyline with rounded 45° bends, interchange rings (Cathedral Sq, Union Cross, Northgate — emerald, amber, azure pips) and square terminal caps. Hand-drawn schematic landmarks (lighthouse, ferry, windmill, cathedral, clock tower, monument, museum, factory, orchard, gate, observatory, stadium) mark every stop. A black train dot with a soft red halo rides the polyline continuously, dwelling at each station while a mechanical flip-board spells the stop name cell by cell and an ETA readout counts down to the terminus. Clicking a station pulses its marker and opens a tiled card with zone chip, first/last times, and next-stop direction; the trip planner highlights the fastest sub-route in emerald with stops/minutes; a 0.2×–3× speed slider retimes the entire line; NIGHT flips the whole board to a dark panel.
TECHNIQUES: SVG path generation with computed 45° bend points, arc-length parameterization of the bent polyline (diagonal + straight remainder) for exact train positioning, station-distance table, dwell state machine with terminus reversal, staggered flip-cell animation via rotateX keyframes, sampled sub-path geometry for trip highlighting, night-mode CSS variable swap plus live SVG re-styling, reduced-motion renders board without spin and slows the line, responsive 980→360 with single-column panel.
INTERACTION: Watch the train run and the flip board announce stations on load. Click any station for its card (name, zone, first/last). Choose origin and destination and press PLAN to light the route in emerald with an ETA. Drag SPEED to retime the line from 0.2× to 3×. Toggle NIGHT for the dark board.