fix off-guard description in detection targeting summary

The detector is off-guard to hidden/undetected creatures (−2 to their
own AC), not the other way around. The hidden creature does not have
−2 AC against the detector's attacks.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

index.html

@@ -507,7 +507,7 @@ flowchart TD
           <li><strong>Undetected:</strong> Declare a square to attack. The GM secretly rolls both the flat check and your attack roll. The GM will not say whether you missed due to the flat check, the attack roll, or choosing the wrong square.</li>
           <li><strong>Unnoticed:</strong> You cannot target the creature directly. Area effects still work normally against undetected creatures.</li>
           <li><strong>Invisible creature</strong> starts as <em>Hidden</em> if you were already observing it when it turned invisible (you last know where it was). It can then Sneak to become Undetected.</li>
-          <li><strong>Off-guard</strong> applies against you when attacking a creature that is hidden or undetected relative to you — it gets the &minus;2 AC penalty.</li>
+          <li><strong>Off-guard:</strong> When a creature is hidden or undetected from you, <em>you</em> are off-guard to <em>it</em> — you take a &minus;2 circumstance penalty to your AC against its attacks. The hidden/undetected creature is not automatically off-guard to you.</li>
         </ul>
       </div>
     </div>