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20px;font-size:14px;font-weight:600}.tab-btn.active{color:var(--accent);border-bottom-color:var(--accent)}.join-code{letter-spacing:12px;text-align:center;color:var(--accent);padding:24px 0;font-family:monospace;font-size:4rem;font-weight:800}.live-question{text-align:center;padding:32px 16px;font-size:1.6rem;font-weight:700}.live-answer-grid{grid-template-columns:1fr 1fr;gap:12px;max-width:600px;margin:0 auto;padding:16px;display:grid}.live-answer-btn{border:2px solid var(--border);border-radius:var(--radius);background:var(--surface);cursor:pointer;text-align:center;padding:20px;font-size:1.1rem;font-weight:600}.live-answer-btn:hover{border-color:var(--accent)}.live-answer-btn.correct{border-color:var(--success);background:#dcfce7}.live-answer-btn.wrong{border-color:var(--danger);background:#fee2e2}.live-waiting{text-align:center;color:var(--muted);padding:48px;font-size:1.2rem}.live-score{text-align:center;padding:16px;font-size:2rem;font-weight:800}.live-participants{flex-wrap:wrap;gap:8px;padding:16px;display:flex}.live-participant-chip{background:var(--accent-soft);color:var(--accent);border-radius:999px;padding:6px 14px;font-size:13px;font-weight:600}.achievement-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px;display:grid}.achievement-card{border-radius:var(--radius-sm);border:1px solid var(--border);background:var(--surface);padding:16px}.achievement-card.earned{border-color:var(--success);background:#f0fdf4}.achievement-card.unearned{opacity:.6}.ach-progress{background:var(--border);border-radius:999px;height:6px;margin-top:8px;overflow:hidden}.ach-progress-fill{background:var(--accent);border-radius:999px;height:100%}.skill-grid{grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:16px;display:grid}.skill-node{border-radius:var(--radius-sm);border:2px solid var(--border);text-align:center;padding:16px}.skill-node.locked{opacity:.4;background:#f1f5f9}.skill-node.available{border-color:var(--accent);background:var(--accent-soft)}.skill-node.completed{border-color:var(--success);background:#f0fdf4}.skill-node.mastered{background:#fffbeb;border-color:#f59e0b}.lb-table{border-collapse:collapse;width:100%}.lb-table th{text-align:left;border-bottom:2px solid var(--border);color:var(--muted);padding:10px 14px;font-size:13px}.lb-table td{border-bottom:1px solid var(--border);padding:10px 14px}.admin-form{flex-wrap:wrap;align-items:flex-end;gap:8px;margin-bottom:16px;display:flex}.admin-list-item{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;padding:10px 0;display:flex}.colour-dot{border-radius:999px;width:16px;height:16px;margin-right:8px;display:inline-block}.phase-indicator{text-align:center;color:var(--accent);text-transform:uppercase;letter-spacing:1px;padding:8px;font-size:14px;font-weight:700}.activity-progress{background:var(--border);border-radius:999px;height:6px;margin-bottom:16px;overflow:hidden}.activity-progress-fill{background:var(--accent);border-radius:999px;height:100%;transition:width .3s}.mc-options{grid-template-columns:1fr 1fr;gap:10px;margin:16px 0;display:grid}.mc-option{border:2px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);cursor:pointer;text-align:center;padding:14px;font-size:15px;font-weight:600}.mc-option:hover{border-color:var(--accent)}.mc-option.correct{border-color:var(--success);background:#dcfce7}.mc-option.wrong{border-color:var(--danger);background:#fee2e2}.daily-challenge{border-radius:var(--radius-sm);border:2px solid var(--warning);background:#fffbeb;padding:16px}.parent-view{max-width:800px;margin:40px auto;padding:0 20px}.parent-stat{text-align:center;color:var(--accent);font-size:2rem;font-weight:800}.parent-label{text-align:center;color:var(--muted);font-size:13px}.chunk-table{border-collapse:collapse;width:100%;margin:12px 0}.chunk-table th,.chunk-table td{border-bottom:1px solid var(--border);text-align:left;padding:8px 12px;font-size:14px}.chunk-table th{color:var(--muted);font-weight:600}.lesson-stage{border:1px solid var(--border);border-radius:var(--radius-sm);margin-bottom:10px;padding:14px}.frame-item{background:var(--bg);border-radius:var(--radius-sm);justify-content:space-between;align-items:center;margin-bottom:6px;padding:8px 12px;display:flex}@media (width<=640px){.live-answer-grid,.mc-options{grid-template-columns:1fr}.join-code{letter-spacing:6px;font-size:2.5rem}.achievement-grid{grid-template-columns:1fr}}.mentor-messages{flex-direction:column;gap:12px;padding:8px 0;display:flex}.mentor-bubble{border-radius:var(--radius-sm);max-width:80%;padding:12px 16px;font-size:14px;line-height:1.5}.mentor-bubble.student{background:var(--accent);color:#fff;border-bottom-right-radius:4px;align-self:flex-end}.mentor-bubble.mentor{background:var(--surface);border:1px solid var(--border);border-bottom-left-radius:4px;align-self:flex-start}.bubble-role{opacity:.7;margin-bottom:4px;font-size:11px;font-weight:700}.bubble-thinking{background:var(--accent-soft);border-radius:var(--radius-sm);color:var(--accent);margin-top:8px;padding:8px 12px;font-size:13px;font-style:italic}.high-contrast{--bg:#000;--surface:#111;--text:#fff;--muted:#ff0;--accent:#0ff;--accent-soft:#033;--border:#fff;--success:#0f0;--danger:red;--warning:#ff0}.high-contrast .sidebar{background:#111;border-color:#fff}.high-contrast .topbar{background:#000;border-color:#fff}.high-contrast .surface{background:#111;border-color:#555}.high-contrast .button{border-color:#fff}.high-contrast input,.high-contrast textarea,.high-contrast select{color:#fff;background:#222;border-color:#555}