## Story 005: Adjust session and break lengths

**Persona:** Casey, 35, a deep-work practitioner who has experimented with 40-minute sessions and 10-minute breaks. The default 25/5 split doesn't fit Casey's rhythm. Casey wants to configure once and then forget about it.

**Situation:**

Casey opens the app's settings. Casey knows exactly what lengths work (40 min session, 10 min break) and wants to set them without friction.

**Need:**

As Casey, I want to adjust the session and break lengths in settings and have those lengths apply to all future sessions, so that I can match the app to my focus rhythm instead of adapting to the app's defaults.

**Acceptance:**
- A Settings screen allows Casey to input custom session length (in minutes)
- The same screen allows Casey to input custom break length
- Settings are saved and apply to the next session started
- Casey can view the current settings at any time to confirm they were saved

**Tier:** core

**Confusion-flags:**
- Should there be a limit on how long a session can be (e.g., max 120 minutes)? Or is that patronizing?
- Should the app warn Casey if they set a very short session (e.g., 1 minute)? Or accept any value?
- If Casey changes settings mid-session, does the current session respect the old length or the new one?
