:root{--primary:#4f46e5;--primary-hover:#4338ca;--primary-light:#e0e7ff;--secondary:#0ea5e9;--bg-main:#f8fafc;--bg-card:#fff;--text-main:#0f172a;--text-muted:#475569;--border-color:#e2e8f0;--success:#16a34a;--danger:#dc2626;--radius:12px;--shadow:0 4px 6px -1px #0000001a, 0 2px 4px -2px #0000000d}*{box-sizing:border-box;margin:0;padding:0}html,body{background-color:var(--bg-main);width:100%;min-height:100vh;color:var(--text-main);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.5;overflow-x:hidden}#root{flex-direction:column;width:100%;min-height:100vh;display:flex}.ispeaker-app{flex-direction:column;gap:24px;width:100%;max-width:1200px;margin:0 auto;padding:16px;display:flex}.ispeaker-header{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px 20px}.header-inner{flex-direction:column;gap:16px;display:flex}@media (width>=768px){.header-inner{flex-direction:row;justify-content:space-between;align-items:center}}.brand-group{flex-direction:column;gap:4px;display:flex}.brand-badge{text-transform:uppercase;background:var(--primary-light);color:var(--primary);border-radius:999px;align-self:flex-start;padding:2px 8px;font-size:11px;font-weight:700;display:inline-block}.brand-title{color:var(--text-main);font-size:1.5rem;font-weight:800}.brand-subtitle{color:var(--text-muted);font-size:.875rem}.status-badge{background:#f1f5f9;border-radius:8px;align-items:center;gap:8px;padding:6px 12px;font-size:.875rem;font-weight:600;display:inline-flex}.ispeaker-nav{flex-wrap:wrap;gap:8px;display:flex}.nav-btn{border:1px solid var(--border-color);min-width:44px;min-height:44px;color:var(--text-main);cursor:pointer;background:#fff;border-radius:8px;padding:8px 16px;font-size:.9rem;font-weight:600;transition:all .2s}.nav-btn:hover,.nav-btn:focus{border-color:var(--primary);outline:2px solid var(--primary);background:#f1f5f9}.nav-btn.active{background:var(--primary);color:#fff;border-color:var(--primary)}.nav-btn.highlight-btn{color:#fff;background:linear-gradient(135deg,#4f46e5,#0ea5e9);border:none}.section-header{margin-bottom:16px}.section-title{color:var(--text-main);margin-bottom:4px;font-size:1.25rem;font-weight:700}.section-desc{color:var(--text-muted);font-size:.9rem}.level-picker-bar{background:var(--bg-card);border-radius:var(--radius);border:1px solid var(--border-color);flex-wrap:wrap;align-items:center;gap:12px;margin-bottom:16px;padding:12px 16px;display:flex}.level-label{font-size:.9rem;font-weight:600}.level-options{flex-wrap:wrap;gap:8px;display:flex}.level-btn{border:1px solid var(--border-color);cursor:pointer;background:#fff;border-radius:8px;min-height:44px;padding:8px 14px;font-size:.85rem;font-weight:600}.level-btn.active{background:var(--secondary);color:#fff;border-color:var(--secondary)}.topic-grid{grid-template-columns:1fr;gap:16px;display:grid}@media (width>=768px){.topic-grid{grid-template-columns:repeat(2,1fr)}}.topic-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow);cursor:pointer;flex-direction:column;gap:12px;padding:20px;transition:transform .15s,border-color .15s;display:flex}.topic-card:hover,.topic-card:focus{border-color:var(--primary);outline:2px solid var(--primary);transform:translateY(-2px)}.topic-card.selected{border:2px solid var(--primary);background:#f5f3ff}.topic-card-header{justify-content:space-between;align-items:center;display:flex}.topic-icon{font-size:1.75rem}.topic-category{text-transform:uppercase;background:var(--primary-light);color:var(--primary);border-radius:6px;padding:2px 8px;font-size:.75rem;font-weight:700}.topic-title{font-size:1.1rem;font-weight:700}.topic-description{color:var(--text-muted);flex-grow:1;font-size:.875rem}.topic-footer{color:var(--text-muted);border-top:1px dashed var(--border-color);justify-content:space-between;align-items:center;padding-top:10px;font-size:.8rem;font-weight:600;display:flex}.select-badge{color:var(--primary)}.phrases-list{flex-direction:column;gap:16px;display:flex}.phrase-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow);gap:16px;padding:16px;display:flex}.phrase-number{color:var(--primary);background:var(--primary-light);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:32px;height:32px;font-size:1.2rem;font-weight:800;display:flex}.phrase-content{flex-direction:column;flex-grow:1;gap:8px;display:flex}.phrase-english-row{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px;display:flex}.phrase-english{color:var(--text-main);font-size:1.05rem;font-weight:700}.speak-btn{border:1px solid var(--primary);min-height:44px;color:var(--primary);cursor:pointer;background:#fff;border-radius:8px;padding:6px 14px;font-size:.85rem;font-weight:600}.speak-btn.playing{background:var(--primary);color:#fff}.phrase-vietnamese{color:var(--text-muted);font-size:.9rem}.phrase-phonetic,.phrase-tip,.phrase-grammar{background:#f1f5f9;border-radius:6px;padding:6px 10px;font-size:.85rem}.practice-phrase-btn{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:8px;min-height:44px;margin-top:8px;padding:8px 16px;font-size:.875rem;font-weight:600}.mic-info-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);flex-direction:column;gap:10px;margin-bottom:16px;padding:16px;display:flex}.info-row{justify-content:space-between;font-size:.9rem;display:flex}.code-pill{background:#e2e8f0;border-radius:4px;padding:2px 6px;font-family:monospace}.mic-controls{justify-content:center;margin:20px 0;display:flex}.record-btn{cursor:pointer;min-width:200px;min-height:52px;box-shadow:var(--shadow);border:none;border-radius:999px;padding:12px 24px;font-size:1rem;font-weight:700}.record-btn.start{background:var(--success);color:#fff}.record-btn.stop{background:var(--danger);color:#fff}@keyframes pulse{0%{opacity:1}50%{opacity:.7}to{opacity:1}}.pulsing{animation:1.5s infinite pulse}.mic-error-toast,.app-toast{color:var(--danger);background:#fef2f2;border:1px solid #fecaca;border-radius:8px;margin-bottom:16px;padding:12px 16px;font-size:.9rem}.bridge-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow);flex-direction:column;gap:20px;padding:24px;display:flex}.summary-grid{grid-template-columns:1fr;gap:12px;display:grid}@media (width>=768px){.summary-grid{grid-template-columns:repeat(2,1fr)}}.summary-item{border:1px solid var(--border-color);background:#f8fafc;border-radius:8px;flex-direction:column;gap:4px;padding:12px;display:flex}.summary-label{color:var(--text-muted);font-size:.8rem;font-weight:600}.summary-value{font-size:.95rem;font-weight:700}.architecture-note{background:#eff6ff;border:1px solid #bfdbfe;border-radius:8px;padding:16px;font-size:.875rem}.architecture-note h4{color:#1e40af;margin-bottom:8px}.architecture-note ul{flex-direction:column;gap:4px;padding-left:20px;display:flex}.launch-btn,.launch-link-btn{cursor:pointer;border:none;border-radius:8px;justify-content:center;align-items:center;min-height:48px;padding:12px 24px;font-size:1rem;font-weight:700;text-decoration:none;display:inline-flex}.launch-btn.primary{background:var(--primary);color:#fff}.launch-link-btn{background:var(--success);color:#fff}.stats-cards-grid{grid-template-columns:1fr;gap:16px;margin-bottom:24px;display:grid}@media (width>=640px){.stats-cards-grid{grid-template-columns:repeat(3,1fr)}}.stat-card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow);align-items:center;gap:16px;padding:20px;display:flex}.stat-icon{font-size:2rem}.stat-body{flex-direction:column;display:flex}.stat-value{color:var(--primary);font-size:1.5rem;font-weight:800}.stat-label{color:var(--text-muted);font-size:.85rem}.daily-stats-table{border-collapse:collapse;background:var(--bg-card);border-radius:var(--radius);border:1px solid var(--border-color);width:100%;margin-top:12px;overflow:hidden}.daily-stats-table th,.daily-stats-table td{text-align:left;border-bottom:1px solid var(--border-color);padding:12px 16px;font-size:.9rem}.daily-stats-table th{background:#f1f5f9;font-weight:700}