• Screen: SCR-PLY.05 — Quiz Player
• Use case: UC-PLY.02 — Take Quiz

Main quiz-taking screen — one question at a time with the response input matching the question type (mcq, multi-select, true/false, fill-blank, matching, short-answer), a server-authoritative countdown timer, a question navigation panel grouped by section, and Previous/Next/Submit actions. Supports per-question auto-save, offline buffer, resume from a saved attempt (cross-device), and auto-submit when time expires. Renders inline within the SCR-PLY.01 viewer area; PLY sidebar and shell remain visible throughout. Mockup shows 3 representative response types (mcq, true/false, multi-select) of the 6 supported by spec.

• lesson_title, quiz_title, attempt_no_label — quiz header, always visible, read-only
• timer_display "Time remaining" — server-authoritative; hidden when no time limit configured
• sync_status_badge — online / offline / syncing
• question_navigator — grouped by section; unanswered/answered/current visual states
• question_number_label, question_points_label, question_text — question content, read-only
• mcq_response / multi_select_response / true_false_response / fill_blank_response / matching_response / short_answer_response — one visible per current_question.type

• navigate_prev "Previous" — enabled when current_question_index > 1 → UC-PLY.02-M-7
• navigate_next "Next" — enabled when current_question_index < total_questions → UC-PLY.02-M-7
• jump_to_question — click any navigator indicator → UC-PLY.02-M-7
• submit "Submit answers" — always enabled → UC-PLY.02-M-9 (may branch to AF-10A)
• confirm_submit "Submit now" — in unanswered warning dialog → UC-PLY.02-A-10A-2
• cancel_submit "Go back and continue" — dismisses the warning dialog, no UC step change

• #modal-unanswered-warning (AF-10A): "You have X unanswered questions — unanswered questions will receive 0 points"; blocks background interaction until the learner chooses.

1. timer_display shows red + pulse when remaining < 60s or < 10% of the time limit; Timer bar hidden when no time limit configured. [SS-PLY.04]
2. When timer reaches 0 (AF-9A): all inputs disabled, full-screen overlay blocks interaction until the system navigates to SCR-PLY.06. [SS-PLY.04]
3. sync_status_badge = offline shows a top banner "Offline — saving answers locally"; timer keeps counting. [SS-PLY.04]
4. Resume notice (AF-2A): banner "Resuming from previous attempt — question X"; auto-dismisses after 4 seconds or on navigation.
5. question_navigator: unanswered = empty circle, answered = filled, current = highlighted ring; responses flushed before navigating (debounce ≤500ms). [SS-PLY.04]
6. Unanswered warning dialog (AF-10A) blocks background interaction until the learner confirms or cancels.