Fix overlap between fishing UI and How to Play instructions

### Build version
Not specified

### Issue Description
When a fishing line is cast, opening the "How to Play" instructions panel causes a UI overlap — both the active fishing net/cast UI and the How to Play instructions are rendered on screen simultaneously, making them visually interfere with each other.

### STR (Steps to Reproduce)
1. Open the app
2. Cast a fishing line
3. While the line is active, click/tap on "How to Play" instructions

### Expected Result
The How to Play instructions should render cleanly over or independently from the fishing UI, without visual overlap or interference.

### Actual Result with evidence
The fishing cast UI (net/line) overlaps with the How to Play instructions panel, making both hard to read/use.

_(Screenshot attached in the original Slack report)_

### Reproduction
Always (100% reproduction rate)

### Operative system and additional Notes
Windows

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Reported by daf

Requested by Dawid Krajewski (<@U079GRD9WTZ>)