As a partial correction:
[before]
(If all coordinates match the correct answer, the game ends, so this rule no longer applies.)
[after]
(If all coordinates match the correct answer at point ②, the distance hint will be displayed as 🎯.)

一部修正：
全座標が正解に一致した場合はゲーム終了ですのでこの限りではありません。
↓
距離については②で全座標が正解に一致した場合は🎯の表示になります。

前回の推測から今回の推測が正解を通り過ぎると、黄色の四角🟨が表示されます。
①→→🎯→→②　：ヒントは🟨
特殊なケースとして座標別のヒントでは、②が正解の場合は🟦、①が正解の場合は🟥になります。全座標が正解に一致した場合はゲーム終了ですのでこの限りではありません。
詳細はマニュアルをご覧ください。
euclidle.com

As a special case for per‑coordinate hints:
- If ② matches the correct value, the hint is 🟦.
- If ① matches the correct value, the hint is 🟥.
(If all coordinates match the correct answer, the game ends, so this rule no longer applies.)
For more details, please refer to the manual.
euclidle.com

When the current guess passes beyond the correct answer, a yellow square 🟨 is shown.
①--->🎯--->②　 Hint: 🟨

When the current guess moves closer to the correct answer compared to the previous guess, a blue square 🟦 is shown.
🎯　②<-----①　 Hint: 🟦
When the current guess moves farther away from the correct answer, a red square 🟥 is shown.
🎯　①----->②　 Hint: 🟥

In the guess history, each coordinate and distance is accompanied by a colored square that serves as a hint.
Below, 🎯 represents the correct answer, ① the previous guess, and ② the current guess.

The square root of this, √5 = 2.236… ≈ 2.24 (rounded to the third decimal place), becomes the Euclidean distance value.

euclidle.com

For example, if the correct answer is (X:7, Y:7, Z:7) and the guess is (X:5, Y:6, Z:7), then (where ^2 denotes squaring):

(7-5)^2 + (7 - 6)^2 + (7 - 7)^2 = 2^2 + 1^2 + 0^2 = 4 + 1 + 0 = 5