A binary search game with zero text hints

Bisect is a visual number guessing game. It hides a target in a range from 1 to 100, and every guess splits that range on screen: the half that cannot hold the target dims out, and the surviving sliver redraws to fill the space. Nothing ever says "too high" or "too low"; you read direction from which side kept its color.

By the fourth guess most people stop doing arithmetic and start halving the range on instinct. That instinct is binary search. Bisect teaches it the way you actually build intuition, by watching a search space collapse instead of reading a rule.

Zero text hints. The bar and its dimming are the only feedback. No "higher or lower," ever.
Three real edge cases. A clean range, a rotated range, and a range with duplicates, the same twists a binary search interview throws at you.
Guess vs. optimal. Each win shows your guess count next to the information-theoretic minimum, ⌈log₂ N⌉.
Plays anywhere. Runs in the browser with no login and no install, on phone and desktop, with synthesized sound you can mute.

Questions

What is Bisect?: A number guessing game where every guess visibly splits a bar and dims the half that can no longer contain the answer. It is a binary search game with no text hints, built to make the algorithm something you can see.
How is this a binary search game?: Binary search finds a value by repeatedly halving a sorted range. In Bisect each guess does exactly that on screen, so playing well is the same as running the algorithm by hand: guess the middle, watch half disappear, repeat.
Why a visual number guessing game instead of "higher or lower"?: Text hints do the search for you and leave nothing behind. A visual number guessing game draws the range you are searching, so the narrowing becomes muscle memory instead of a sentence you skim.
What do the later levels add?: Level 2 rotates the range so ascending order no longer matches screen position, and Level 3 fills it with duplicates so a single guess does not always cut the space cleanly. Both are classic binary search interview variants, taught the same visual way.
Do I need to know how to code?: No. The whole game is visual and language-free. It helps programmers feel an algorithm they already know, but anyone who can find a number between 1 and 100 can play.

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