.lesson-generator{margin:40px 0}.generator-trigger{display:flex;flex-direction:column;align-items:center;justify-content:center;width:100%;max-width:400px;margin:0 auto;padding:30px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:20px;cursor:pointer;transition:all .3s ease;box-shadow:0 8px 25px #667eea4d;position:relative;overflow:hidden}.generator-trigger:hover{transform:translateY(-3px);box-shadow:0 12px 35px #667eea66}.generator-trigger:before{content:"";position:absolute;inset:0;background:linear-gradient(45deg,transparent 30%,rgba(255,255,255,.1) 50%,transparent 70%);transform:translate(-100%);transition:transform .6s ease}.generator-trigger:hover:before{transform:translate(100%)}.trigger-icon{font-size:3rem;margin-bottom:10px;animation:sparkle 2s ease-in-out infinite}@keyframes sparkle{0%,to{transform:scale(1) rotate(0)}50%{transform:scale(1.1) rotate(5deg)}}.trigger-text{font-size:1.5rem;font-weight:700;margin-bottom:5px}.trigger-subtitle{font-size:1rem;opacity:.9;font-weight:500}.generator-modal{position:fixed;inset:0;z-index:2000;display:flex;align-items:center;justify-content:center;padding:20px}.modal-overlay{position:absolute;inset:0;background:#000000b3;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}.modal-content{position:relative;background:#fff;border-radius:20px;max-width:900px;width:100%;max-height:90vh;overflow-y:auto;box-shadow:0 20px 60px #0000004d;animation:modalSlideIn .3s ease-out}@keyframes modalSlideIn{0%{opacity:0;transform:translateY(30px) scale(.95)}to{opacity:1;transform:translateY(0) scale(1)}}.modal-close{position:absolute;top:20px;right:20px;background:#0000001a;border:none;width:40px;height:40px;border-radius:50%;font-size:1.5rem;color:#666;cursor:pointer;transition:all .2s ease;z-index:10}.modal-close:hover{background:#0003;color:#333}.generator-form{padding:40px}.form-header{text-align:center;margin-bottom:40px}.form-header h3{font-size:2rem;color:#333;margin-bottom:10px}.form-header p{color:#666;font-size:1.1rem}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-bottom:30px}.form-group{display:flex;flex-direction:column}.form-group label{display:flex;flex-direction:column;width:100%}.label-text{font-weight:600;color:#374151;margin-bottom:8px;display:block}.form-input,.form-select,.form-textarea{width:100%;padding:12px 16px;border:2px solid #e5e7eb;border-radius:12px;font-size:1rem;transition:all .2s ease;background:#fff;box-sizing:border-box}.form-input:focus,.form-select:focus,.form-textarea:focus{outline:none;border-color:#667eea;box-shadow:0 0 0 3px #667eea1a}.form-textarea{resize:vertical;font-family:inherit}.struggles-section{margin:40px 0;padding:30px;background:linear-gradient(135deg,#f8fafc,#f1f5f9);border-radius:16px;border:1px solid #e2e8f0}.struggles-section h4{color:#1e293b;font-size:1.3rem;margin-bottom:8px}.struggles-hint{color:#64748b;margin-bottom:20px}.struggles-grid{display:grid;grid-template-columns:1fr;gap:20px}.error-message{display:flex;align-items:center;gap:10px;background:#fef2f2;color:#dc2626;padding:15px;border-radius:12px;border:1px solid #fecaca;margin:20px 0}.error-icon{font-size:1.2rem}.error-help{margin-top:15px;padding-top:15px;border-top:1px solid #fecaca}.error-help p{margin-bottom:10px;font-weight:600}.error-help ol{margin:0;padding-left:20px}.error-help li{margin-bottom:5px}.error-help a{color:#dc2626;text-decoration:underline}.form-actions{text-align:center;margin-top:30px}.generate-btn{background:linear-gradient(135deg,#10b981,#059669);color:#fff;border:none;padding:16px 40px;border-radius:50px;font-size:1.1rem;font-weight:600;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 15px #10b9814d}.generate-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 6px 20px #10b98166}.generate-btn:disabled{opacity:.6;cursor:not-allowed;transform:none}.generating-state{padding:60px 40px;text-align:center}.generating-animation{margin-bottom:30px}.ai-brain{font-size:4rem;animation:brainPulse 2s ease-in-out infinite}@keyframes brainPulse{0%,to{transform:scale(1)}50%{transform:scale(1.1)}}.generating-dots{display:flex;justify-content:center;gap:8px;margin-top:20px}.generating-dots span{width:12px;height:12px;background:#667eea;border-radius:50%;animation:dotBounce 1.4s ease-in-out infinite both}.generating-dots span:nth-child(1){animation-delay:-.32s}.generating-dots span:nth-child(2){animation-delay:-.16s}.generating-dots span:nth-child(3){animation-delay:0}@keyframes dotBounce{0%,80%,to{transform:scale(0)}40%{transform:scale(1)}}.generating-state h3{font-size:1.8rem;color:#333;margin-bottom:10px}.generating-state p{color:#666;font-size:1.1rem;margin-bottom:30px}.generating-steps{display:flex;flex-direction:column;gap:10px;max-width:300px;margin:0 auto}.step{padding:12px 20px;background:#f8fafc;border-radius:8px;color:#64748b;transition:all .3s ease}.step.active{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;transform:translate(5px)}.lesson-preview{max-height:90vh;overflow-y:auto}.preview-header{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:30px 40px;text-align:center}.preview-header h3{font-size:1.8rem;margin-bottom:15px}.lesson-meta{display:flex;justify-content:center;gap:30px;opacity:.9}.lesson-title{font-weight:600}.lesson-sections{font-size:.9rem}.preview-actions{display:flex;justify-content:center;gap:15px;padding:20px 40px;background:#f8fafc;border-bottom:1px solid #e2e8f0}.action-btn{padding:10px 20px;border:none;border-radius:8px;font-weight:600;cursor:pointer;transition:all .2s ease}.action-btn.save{background:#10b981;color:#fff}.action-btn.share{background:#3b82f6;color:#fff}.action-btn.reset{background:#6b7280;color:#fff}.action-btn:hover{transform:translateY(-1px);box-shadow:0 4px 12px #00000026}.lesson-container{padding:0;background:#fff}.saved-state{padding:60px 40px;text-align:center}.success-animation{font-size:4rem;margin-bottom:20px;animation:successPulse 1s ease-out}@keyframes successPulse{0%{transform:scale(0)}50%{transform:scale(1.2)}to{transform:scale(1)}}.saved-state h3{font-size:1.8rem;color:#059669;margin-bottom:10px}.saved-state p{color:#666;margin-bottom:30px}.saved-actions{display:flex;justify-content:center;gap:15px}@media (max-width: 768px){.modal-content{margin:10px;max-height:95vh}.generator-form{padding:30px 20px}.form-grid{grid-template-columns:1fr}.preview-actions{flex-direction:column;align-items:center}.lesson-meta{flex-direction:column;gap:10px}.saved-actions{flex-direction:column;align-items:center}}.lesson-index{min-height:100vh;background:linear-gradient(135deg,#667eea,#764ba2);padding-bottom:60px}.index-header{background:#ffffff1a;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-bottom:1px solid rgba(255,255,255,.2);padding:40px 20px;margin-bottom:40px}.header-content{max-width:1200px;margin:0 auto;text-align:center}.index-header h1{color:#fff;font-size:3rem;margin-bottom:10px;text-shadow:2px 2px 4px rgba(0,0,0,.2)}.subtitle{color:#ffffffe6;font-size:1.2rem;margin-bottom:30px}.overall-progress{max-width:600px;margin:0 auto}.stats-row{display:flex;justify-content:space-around;margin-bottom:20px;gap:20px}.stat{display:flex;flex-direction:column;align-items:center;background:#ffffff26;padding:15px 25px;border-radius:10px;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.stat-value{font-size:2rem;font-weight:700;color:#fff}.stat-label{font-size:.9rem;color:#fffc;margin-top:5px}.progress-bar-main{height:30px;background:#fff3;border-radius:15px;overflow:hidden;position:relative}.progress-fill-main{height:100%;background:linear-gradient(90deg,#4ade80,#22d3ee);transition:width .5s ease;display:flex;align-items:center;justify-content:flex-end;padding-right:10px;color:#fff;font-weight:700}.user-info{position:absolute;top:20px;right:20px;background:#fff3;padding:10px 20px;border-radius:20px;color:#fff;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.category-tabs{display:flex;justify-content:center;gap:10px;margin-bottom:40px;padding:0 20px}.category-tabs button{padding:12px 25px;background:#ffffff1a;border:2px solid rgba(255,255,255,.3);color:#fff;border-radius:25px;cursor:pointer;transition:all .3s ease;font-size:1rem;font-weight:500}.category-tabs button:hover{background:#fff3;transform:translateY(-2px)}.category-tabs button.active{background:#ffffff40;border-color:#fff;box-shadow:0 4px 12px #0003}.content-sections{max-width:1200px;margin:0 auto;padding:0 20px}.content-section{margin-bottom:60px}.section-header{text-align:center;margin-bottom:30px}.section-header h2{color:#fff;font-size:2rem;margin-bottom:10px}.section-header p{color:#fffc;font-size:1.1rem}.content-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(350px,1fr));gap:25px}.content-card{background:#fff;border-radius:15px;padding:25px;text-decoration:none;color:#333;transition:all .3s ease;box-shadow:0 4px 6px #0000001a;display:flex;flex-direction:column;position:relative;overflow:hidden}.content-card:hover{transform:translateY(-5px);box-shadow:0 12px 24px #0003}.content-card.keynote{background:linear-gradient(135deg,#fff,#fef3c7);border:2px solid #fbbf24}.content-card.lesson{background:linear-gradient(135deg,#fff,#e0f2fe)}.content-card.demo{background:linear-gradient(135deg,#fff,#f0fdf4);border:2px solid #4ade80}.card-header{display:flex;justify-content:space-between;align-items:flex-start;margin-bottom:15px}.card-header h3{font-size:1.3rem;color:#1f2937;margin:0;flex-grow:1}.keynote-badge{background:linear-gradient(135deg,#fbbf24,#f59e0b);color:#fff;padding:4px 12px;border-radius:12px;font-size:.85rem;font-weight:700;white-space:nowrap}.badge{padding:4px 12px;border-radius:12px;font-size:.85rem;font-weight:700;white-space:nowrap}.badge.completed{background:#4ade80;color:#fff}.badge.in-progress{background:#60a5fa;color:#fff}.badge.not-started{background:#e5e7eb;color:#6b7280}.card-description{color:#4b5563;line-height:1.6;margin-bottom:20px;flex-grow:1}.card-footer{display:flex;justify-content:space-between;align-items:center;padding-top:15px;border-top:1px solid #e5e7eb}.duration{color:#6b7280;font-size:.9rem}.progress-bar-mini{width:150px;height:20px;background:#e5e7eb;border-radius:10px;overflow:hidden;position:relative}.progress-fill-mini{height:100%;background:linear-gradient(90deg,#4ade80,#22d3ee);transition:width .5s ease}.progress-text-mini{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);font-size:.75rem;font-weight:700;color:#333}.keynote-features{display:flex;gap:10px;margin-top:15px}.keynote-features .feature{background:#fbbf241a;color:#f59e0b;padding:6px 12px;border-radius:8px;font-size:.85rem;font-weight:500}.generator-section-top{max-width:1200px;margin:40px auto;padding:0 20px}.quick-actions{display:flex;justify-content:center;gap:20px;margin-top:60px;padding:0 20px}.action-btn{padding:15px 40px;font-size:1.1rem;font-weight:700;border:none;border-radius:30px;cursor:pointer;transition:all .3s ease}.action-btn.primary{background:#fff;color:#764ba2;box-shadow:0 4px 12px #0003}.action-btn.primary:hover{transform:translateY(-2px);box-shadow:0 6px 20px #0000004d}.action-btn.secondary{background:#fff3;color:#fff;border:2px solid white}.action-btn.secondary:hover{background:#ffffff4d;transform:translateY(-2px)}@media (max-width: 768px){.index-header h1{font-size:2rem}.content-grid{grid-template-columns:1fr}.category-tabs{flex-wrap:wrap}.stats-row{flex-direction:column}.user-info{position:static;margin-top:20px;display:inline-block}}*{margin:0;padding:0;box-sizing:border-box}body{font-family:SF Pro Display,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:linear-gradient(135deg,#667eea,#764ba2);min-height:100vh;color:#333;overflow-x:hidden;position:relative}body:before{content:"";position:fixed;top:0;left:0;width:100%;height:100%;background:linear-gradient(135deg,#667eea66,#764ba266,#8b5cf666);animation:gradientShift 20s ease-in-out infinite;z-index:-2}body:after{content:"";position:fixed;top:0;left:0;width:100%;height:100%;background-image:radial-gradient(circle at 20% 80%,rgba(255,255,255,.04) 0%,transparent 50%),radial-gradient(circle at 80% 20%,rgba(255,255,255,.03) 0%,transparent 50%),radial-gradient(circle at 40% 40%,rgba(255,255,255,.02) 0%,transparent 50%);animation:floatingOrbs 30s linear infinite;pointer-events:none;z-index:-1}@keyframes gradientShift{0%,to{background:linear-gradient(135deg,#667eea66,#764ba266,#8b5cf666)}25%{background:linear-gradient(135deg,#8b5cf666,#667eea66,#a855f766)}50%{background:linear-gradient(135deg,#a855f766,#8b5cf666,#7c3aed66)}75%{background:linear-gradient(135deg,#7c3aed66,#a855f766,#667eea66)}}@keyframes floatingOrbs{0%{transform:translate(0) translateY(0) rotate(0)}33%{transform:translate(-20px) translateY(-20px) rotate(120deg)}66%{transform:translate(20px) translateY(-10px) rotate(240deg)}to{transform:translate(0) translateY(0) rotate(360deg)}}@keyframes shimmer{0%{left:-100%}to{left:100%}}@keyframes subtlePulse{0%,to{box-shadow:0 20px 40px #0000001a}50%{box-shadow:0 25px 50px #6366f126}}@keyframes completionGlow{0%,to{box-shadow:0 20px 40px #0000001a}50%{box-shadow:0 25px 50px #10b98133}}.loading-container{display:flex;justify-content:center;align-items:center;height:100vh}.loading-spinner{font-size:18px;color:#fff;font-weight:600}.auth-container{max-width:400px;margin:100px auto;padding:40px;background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:24px;box-shadow:0 20px 40px #0000001a}.auth-title{text-align:center;font-size:28px;font-weight:700;color:#1f2937;margin-bottom:30px}.auth-input{width:100%;padding:15px;margin-bottom:20px;border:2px solid #e2e8f0;border-radius:12px;font-size:16px;background:#fff}.auth-input:focus{outline:none;border-color:#6366f1}.auth-btn{width:100%;padding:15px;background:linear-gradient(135deg,#6366f1,#8b5cf6);color:#fff;border:none;border-radius:12px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;margin-bottom:15px}.auth-btn:hover{transform:translateY(-2px);box-shadow:0 8px 24px #6366f166}.auth-btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.auth-toggle{text-align:center;color:#6b7280;cursor:pointer;font-size:14px}.auth-toggle:hover{color:#6366f1}.error-message{color:#dc2626;font-size:14px;margin-bottom:15px;text-align:center}.container{max-width:800px;margin:0 auto;padding:40px 24px;width:100%;box-sizing:border-box}@media (max-width: 768px){.container{padding:16px 16px 120px}}@media (max-width: 480px){.container{padding:12px 12px 120px}}.lesson-card{background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:24px;padding:32px;margin-bottom:30px;box-shadow:0 20px 40px #0000001a;border:1px solid rgba(255,255,255,.2);width:100%;box-sizing:border-box;animation:lessonCardFloat 6s ease-in-out infinite;transform-origin:center}@keyframes lessonCardFloat{0%,to{transform:translateY(0) scale(1)}50%{transform:translateY(-5px) scale(1.002)}}@media (min-width: 1200px){.lesson-card{padding:40px}}@media (max-width: 768px){.lesson-card{padding:24px;margin-bottom:20px;border-radius:18px}.lesson-number{font-size:12px;padding:6px 12px;letter-spacing:1.5px}}@media (max-width: 480px){.lesson-card{padding:20px;margin-bottom:16px;border-radius:16px}.lesson-number{font-size:11px;padding:5px 10px;letter-spacing:1px;margin-bottom:8px}.lesson-title{font-size:28px}.lesson-subtitle{font-size:16px}}.lesson-header{text-align:center;margin-bottom:40px;display:flex;flex-direction:column;align-items:center}.lesson-title{font-size:32px;font-weight:700;color:#1f2937;margin-bottom:15px}.lesson-subtitle{font-size:18px;color:#6b7280;font-weight:400}.logout-btn{position:fixed;top:20px;right:20px;background:#ffffffe6;border:none;border-radius:12px;padding:10px 20px;cursor:pointer;font-weight:600;color:#6b7280;transition:all .3s ease}.logout-btn:hover{background:#fff;color:#6366f1}.user-info{margin-bottom:30px;padding:20px;background:#6366f11a;border-radius:12px;text-align:center}.ai-test-buttons{display:flex;gap:15px;justify-content:center;margin-top:30px;flex-wrap:wrap}.test-btn{padding:12px 24px;background:linear-gradient(135deg,#10b981,#059669);color:#fff;border:none;border-radius:8px;font-weight:600;cursor:pointer;transition:all .3s ease}.test-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px #10b98166}.api-key-manager{background:#6366f10d;border-radius:16px;padding:30px;margin:30px 0}.manager-title{font-size:20px;font-weight:600;color:#1f2937;margin-bottom:10px}.manager-subtitle{color:#6b7280;margin-bottom:25px}.provider-selection{background:#fffc;border-radius:12px;padding:20px;margin-bottom:25px;border:1px solid rgba(99,102,241,.2)}.provider-selection label{display:block;font-weight:600;color:#1f2937;margin-bottom:10px;font-size:14px}.provider-dropdown{width:100%;padding:12px 16px;border:2px solid #e5e7eb;border-radius:8px;font-size:15px;color:#1f2937;background-color:#fff;cursor:pointer;transition:all .3s ease}.provider-dropdown:hover{border-color:#8b5cf6}.provider-dropdown:focus{outline:none;border-color:#8b5cf6;box-shadow:0 0 0 3px #8b5cf61a}.provider-dropdown option:disabled{color:#9ca3af}.provider-hint{margin-top:10px;font-size:13px;color:#6b7280;font-style:italic}.key-inputs{display:flex;flex-direction:column;gap:20px;margin-bottom:25px}.key-input-group{display:flex;flex-direction:column;gap:8px}.key-input-group label{font-weight:500;color:#4b5563;font-size:14px}.input-wrapper{display:flex;gap:10px;align-items:center}.api-key-input{flex:1;padding:12px;border:2px solid #e2e8f0;border-radius:8px;font-family:monospace;font-size:14px}.api-key-input:focus{outline:none;border-color:#6366f1}.toggle-visibility{background:none;border:1px solid #e2e8f0;border-radius:6px;padding:8px 12px;cursor:pointer;font-size:16px;transition:all .2s ease}.toggle-visibility:hover{background:#f3f4f6}.clear-keys-btn{background:#ef4444;color:#fff;border:none;border-radius:8px;padding:10px 20px;font-weight:500;cursor:pointer;transition:all .3s ease}.clear-keys-btn:hover{background:#dc2626;transform:translateY(-1px)}.privacy-note{margin-top:20px;padding:15px;background:#10b9811a;border-radius:8px;font-size:14px;color:#047857}.auth-toggle-btn{position:fixed;top:20px;right:20px;background:linear-gradient(135deg,#6366f1,#8b5cf6);color:#fff;border:none;border-radius:12px;padding:12px 24px;cursor:pointer;font-weight:600;transition:all .3s ease;z-index:100}.auth-toggle-btn:hover{transform:translateY(-2px);box-shadow:0 8px 24px #6366f166}.test-section{margin-top:40px;padding-top:30px;border-top:1px solid #e2e8f0}.test-section h3{margin-bottom:20px;font-size:18px;font-weight:600;color:#1f2937}.test-result{margin-top:15px;padding:12px;background:#f9fafb;border-radius:8px;font-size:14px;color:#374151}.auth-prompt{text-align:center;margin-top:40px;padding-top:30px;border-top:1px solid #e2e8f0;color:#6b7280}.auth-prompt a{color:#6366f1;text-decoration:none;font-weight:500}.auth-prompt a:hover{text-decoration:underline}.progress-bar{position:fixed;top:0;left:0;width:100%;height:8px;background:#0000001a;z-index:999;overflow:hidden;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px)}.progress-fill{height:100%;background:linear-gradient(90deg,#10b981,#059669);transition:width .8s cubic-bezier(.4,0,.2,1);width:0%;box-shadow:0 0 15px #10b9814d}body.dark-mode .progress-bar{background:#ffffff1a}.settings-section{border-bottom:1px solid #e5e7eb;padding-bottom:16px;margin-bottom:16px}.settings-controls{display:flex;flex-direction:column;gap:8px}.setting-btn{display:flex;align-items:center;gap:12px;background:#f9fafb;border:1px solid #e5e7eb;border-radius:8px;padding:12px 16px;color:#374151;cursor:pointer;transition:all .2s ease;font-size:14px;font-weight:500;width:100%;text-align:left}.setting-btn:hover{background:#f3f4f6;border-color:#d1d5db;transform:translateY(-1px)}.setting-icon{font-size:16px;width:20px;text-align:center}.setting-label{flex:1}body.dark-mode .settings-section{border-color:#374151;background:#1e293b}body.dark-mode .setting-btn{background:#374151;border-color:#4b5563;color:#f9fafb}body.dark-mode .setting-btn:hover{background:#4b5563;border-color:#6b7280}.api-settings{position:fixed;top:80px;right:20px;background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:16px;padding:24px;box-shadow:0 10px 30px #0000001a;border:1px solid rgba(255,255,255,.2);z-index:1000;width:320px;transform:translate(calc(100% + 40px));transition:transform .3s cubic-bezier(.4,0,.2,1);opacity:0;visibility:hidden}.api-settings.open{transform:translate(0);opacity:1;visibility:visible}body.dark-mode .api-settings{background:#1e293bf2;border-color:#ffffff1a;box-shadow:0 10px 30px #0000004d}.api-settings h3{margin-bottom:20px;color:#374151;font-size:18px;font-weight:600}body.dark-mode .api-settings h3{color:#f1f5f9}.api-settings label{display:block;margin-bottom:6px;font-weight:600;color:#6b7280;font-size:14px}body.dark-mode .api-settings label{color:#94a3b8}.api-input{width:100%;padding:10px;border:2px solid #e2e8f0;border-radius:8px;margin-bottom:15px;font-size:14px}.api-input:focus{outline:none;border-color:#6366f1}body.dark-mode .api-input{background:#1e293b;border-color:#475569;color:#f1f5f9}body.dark-mode .api-input::placeholder{color:#94a3b8}.save-keys-btn{width:100%;padding:12px;background:linear-gradient(135deg,#6366f1,#8b5cf6);color:#fff;border:none;border-radius:10px;font-weight:600;cursor:pointer;font-size:14px;transition:all .2s ease}.save-keys-btn:hover{transform:translateY(-1px);box-shadow:0 4px 12px #6366f14d}body.dark-mode .lesson-card{background:#1e293bf2;border-color:#ffffff1a;box-shadow:0 20px 40px #0000004d}.lesson-number{font-size:14px;font-weight:600;color:#6366f1;text-transform:uppercase;letter-spacing:2px;margin-bottom:10px;background:linear-gradient(135deg,#eef2ff,#e0e7ff);padding:8px 16px;border-radius:20px;display:inline-block;border:1px solid rgba(99,102,241,.2);transition:all .3s ease;animation:fadeIn .6s ease-out}.lesson-number:hover{transform:translateY(-2px);box-shadow:0 4px 12px #6366f126}body.dark-mode .lesson-number{color:#818cf8;background:linear-gradient(135deg,#312e81,#3730a3);border-color:#818cf84d}body.dark-mode .lesson-title{color:#f1f5f9}body.dark-mode .lesson-subtitle{color:#94a3b8}.content-section{margin-bottom:30px}.content-section.full-width{margin-left:-24px;margin-right:-24px;padding:0 24px}@media (min-width: 768px){.content-section.full-width{margin-left:-32px;margin-right:-32px;padding:0 32px}}@media (min-width: 1024px){.content-section.full-width{margin-left:-40px;margin-right:-40px;padding:0 40px}}.section-title{font-size:20px;font-weight:600;color:#374151;margin-bottom:15px;padding-bottom:8px;border-bottom:2px solid #e5e7eb}body.dark-mode .section-title{color:#e2e8f0;border-bottom-color:#374151}.important-text{background:linear-gradient(135deg,#fef3c7,#fde68a);padding:24px;border-radius:16px;margin:24px 0;border-left:4px solid #f59e0b;font-weight:500;color:#92400e;line-height:1.6;box-shadow:0 4px 16px #f59e0b1a}body.dark-mode .important-text{background:linear-gradient(135deg,#451a03,#78350f);border-left-color:#d97706;color:#fcd34d}.unlock-message{background:linear-gradient(135deg,#fef3c7,#fde68a);border:2px solid #f59e0b;border-radius:12px;padding:15px 20px;margin:20px 0;text-align:center;font-weight:500;color:#92400e}body.dark-mode .unlock-message{background:linear-gradient(135deg,#451a03,#78350f);border-color:#d97706;color:#fcd34d}.dos-donts{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:24px;margin:30px 0;width:100%}@media (max-width: 768px){.dos-donts{gap:20px}}@media (max-width: 640px){.dos-donts{grid-template-columns:1fr;gap:16px}}.dos,.donts{padding:28px;border-radius:18px;border:2px solid transparent;position:relative;overflow:hidden;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 16px #0000000d;animation:subtlePulse 8s ease-in-out infinite}.dos.completed,.donts.completed{animation:completionGlow 4s ease-in-out infinite}@media (min-width: 1024px){.dos,.donts{padding:32px}}@media (max-width: 768px){.dos,.donts{padding:24px}}.dos{background:linear-gradient(135deg,#ecfdf5,#d1fae5);border-color:#10b981}.donts{background:linear-gradient(135deg,#fef2f2,#fecaca);border-color:#ef4444}body.dark-mode .dos{background:linear-gradient(135deg,#064e3b,#065f46);border-color:#10b981}body.dark-mode .donts{background:linear-gradient(135deg,#7f1d1d,#991b1b);border-color:#ef4444}.dos:hover,.donts:hover{transform:translateY(-2px);box-shadow:0 10px 25px #0000001a}.dos h3,.donts h3{font-size:20px;font-weight:600;margin-bottom:16px;display:flex;align-items:center;gap:10px;position:relative;color:inherit}.dos h3:after,.donts h3:after{content:"▼";font-size:14px;transition:transform .3s ease;margin-left:auto;color:inherit}.dos.expanded h3:after,.donts.expanded h3:after{transform:rotate(180deg)}.dos h3{color:#059669}.donts h3{color:#dc2626}body.dark-mode .dos h3{color:#34d399}body.dark-mode .donts h3{color:#fca5a5}.dos ul,.donts ul{list-style:none;padding:0;max-height:0;overflow:hidden;transition:max-height .4s ease,opacity .3s ease;opacity:0}.dos.expanded ul,.donts.expanded ul{max-height:600px;opacity:1}.dos li,.donts li{margin-bottom:14px;padding-left:24px;position:relative;line-height:1.7;font-size:15px;transform:translateY(-10px);transition:transform .3s ease;color:#374151}.dos.expanded li,.donts.expanded li{transform:translateY(0)}body.dark-mode .dos li,body.dark-mode .donts li{color:#d1d5db}.dos li:before{content:"✓";position:absolute;left:0;color:#059669;font-weight:700}.donts li:before{content:"✗";position:absolute;left:0;color:#dc2626;font-weight:700}.question-container{background:#f8fafc;border-radius:18px;padding:28px;margin:28px 0;border:2px solid #e2e8f0;opacity:.5;pointer-events:none;transition:all .3s ease;box-shadow:0 4px 16px #0000000d}.question-container.unlocked{opacity:1;pointer-events:auto}body.dark-mode .question-container{background:#334155;border-color:#475569;color:#f1f5f9}.question-title{font-size:18px;font-weight:600;color:#1e293b;margin-bottom:15px}body.dark-mode .question-title{color:#f1f5f9}.question-options{display:flex;flex-direction:column;gap:12px}.option{background:#fff;border:2px solid #e2e8f0;border-radius:10px;padding:15px 20px;cursor:pointer;transition:all .3s ease;position:relative;overflow:hidden}.option:hover{border-color:#6366f1;transform:translateY(-2px);box-shadow:0 10px 25px #6366f126}.option.selected{border-color:#6366f1;background:#eef2ff}.option.correct{border-color:#10b981;background:#ecfdf5}.option.incorrect{border-color:#ef4444;background:#fef2f2}body.dark-mode .option{background:#1e293b;border-color:#475569;color:#f1f5f9}body.dark-mode .option:hover{border-color:#6366f1;background:#334155}.explanation-container{margin-top:20px;padding:20px;background:linear-gradient(135deg,#fef3c7,#fde68a);border-radius:16px;border:2px solid #fbbf24;animation:fadeIn .5s ease-out}body.dark-mode .explanation-container{background:linear-gradient(135deg,#78350f,#92400e);border-color:#f59e0b}.explanation-header{font-size:16px;font-weight:600;color:#92400e;margin-bottom:12px}body.dark-mode .explanation-header{color:#fde68a}.explanation-text{font-size:15px;line-height:1.6;color:#78350f;margin-bottom:16px}body.dark-mode .explanation-text{color:#fef3c7}.correct-answer-hint{font-size:14px;color:#92400e;padding-top:12px;border-top:1px solid #fbbf24}body.dark-mode .correct-answer-hint{color:#fde68a;border-top-color:#f59e0b}.error-container{background:#fef2f2;border:2px solid #fecaca;border-radius:12px;padding:20px;margin-top:20px;animation:fadeIn .3s ease-out}body.dark-mode .error-container{background:#7f1d1d;border-color:#dc2626}.error-message{color:#991b1b;font-size:15px;line-height:1.5;margin-bottom:15px}body.dark-mode .error-message{color:#fecaca}.error-icon{margin-right:8px;font-size:18px}.retry-button{background:#dc2626;color:#fff;border:none;padding:10px 20px;border-radius:8px;font-size:14px;font-weight:600;cursor:pointer;transition:all .2s ease}.retry-button:hover:not(:disabled){background:#b91c1c;transform:translateY(-2px)}.retry-button:disabled{opacity:.5;cursor:not-allowed}.rate-limit-info{margin-top:12px;font-size:14px;color:#7c2d12;font-style:italic}body.dark-mode .rate-limit-info{color:#fed7aa}.completion-check{display:inline-block;width:24px;height:24px;background:#10b981;color:#fff;border-radius:50%;text-align:center;line-height:24px;font-size:14px;font-weight:700;margin-left:10px;animation:bounceIn .6s ease-out}@keyframes bounceIn{0%{transform:scale(0);opacity:0}50%{transform:scale(1.2)}to{transform:scale(1);opacity:1}}.dos.completed,.donts.completed,.formats.completed,.challenges.completed{border-color:#10b981;position:relative;overflow:visible}.dos.completed:after,.donts.completed:after,.formats.completed:after,.challenges.completed:after{content:"";position:absolute;inset:-2px;background:linear-gradient(45deg,#10b981,#34d399);border-radius:inherit;opacity:.2;animation:pulse 2s ease-in-out infinite;z-index:-1}@keyframes pulse{0%,to{opacity:.2}50%{opacity:.4}}.just-completed{animation:celebrateCompletion 1s ease-out}@keyframes celebrateCompletion{0%{transform:scale(1)}25%{transform:scale(1.05);box-shadow:0 0 20px #10b98180}50%{transform:scale(1.02)}to{transform:scale(1)}}.question-container.completed{border-color:#10b981;box-shadow:0 4px 16px #10b98133}.interactive-title .completion-check{vertical-align:middle;margin-left:12px}.lesson-transition{position:relative;transition:all .3s ease-out;transform:translate(0);opacity:1}.lesson-transition.transitioning.forward{transform:translate(-50px);opacity:0}.lesson-transition.transitioning.backward{transform:translate(50px);opacity:0}@keyframes slideInFromRight{0%{transform:translate(100px);opacity:0}to{transform:translate(0);opacity:1}}@keyframes slideInFromLeft{0%{transform:translate(-100px);opacity:0}to{transform:translate(0);opacity:1}}.lesson-card{animation:slideInFromRight .5s ease-out}.lesson-card.visible{opacity:1;transform:translateY(0)}.transition-loader{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:300px;animation:fadeIn .3s ease-out}.loading-spinner{width:50px;height:50px;border:5px solid rgba(102,102,239,.2);border-top-color:#6666ef;border-radius:50%;animation:spin 1s linear infinite;margin-bottom:20px}.transition-loader p{color:#6666ef;font-size:16px;font-weight:500}.mc-to-model{background:linear-gradient(135deg,#f8fafc,#e2e8f0);border-radius:18px;padding:28px;margin:28px 0;border:2px solid #cbd5e1;opacity:.5;pointer-events:none;transition:all .3s ease;box-shadow:0 4px 16px #0000000d}.mc-to-model.unlocked{opacity:1;pointer-events:auto}body.dark-mode .mc-to-model{background:linear-gradient(135deg,#334155,#475569);border-color:#64748b;color:#f1f5f9}.mc-question-title{font-size:18px;font-weight:600;color:#1e293b;margin-bottom:20px;text-align:center}body.dark-mode .mc-question-title{color:#f1f5f9}.mc-options-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:24px}@media (max-width: 768px){.mc-options-grid{grid-template-columns:1fr;gap:12px}}.mc-option{background:#fff;border:2px solid #e2e8f0;border-radius:12px;padding:16px;cursor:pointer;transition:all .3s ease;position:relative}.mc-option:hover{border-color:#6366f1;box-shadow:0 4px 12px #6366f11a;transform:translateY(-2px)}.mc-option.selected{border-color:#6366f1;background:#eef2ff}.mc-option.selected.correct{border-color:#10b981;background:#ecfdf5}.mc-option.selected.incorrect{border-color:#ef4444;background:#fef2f2}body.dark-mode .mc-option{background:#1e293b;border-color:#475569;color:#f1f5f9}.option-label{font-size:12px;font-weight:600;color:#6366f1;text-transform:uppercase;margin-bottom:8px}.option-text{font-size:14px;line-height:1.5;color:#374151}body.dark-mode .option-text{color:#d1d5db}.comparison-section{margin-top:32px;padding-top:32px;border-top:2px solid #e2e8f0;animation:fadeIn .5s ease-out}body.dark-mode .comparison-section{border-top-color:#475569}.comparison-header{text-align:center;margin-bottom:24px}.comparison-header h4{font-size:20px;color:#1e293b;margin-bottom:8px}.comparison-header p{color:#6b7280;font-size:14px}body.dark-mode .comparison-header h4{color:#f1f5f9}body.dark-mode .comparison-header p{color:#9ca3af}.provider-responses{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:20px;margin-bottom:24px}.provider-response{background:#fff;border-radius:12px;padding:20px;border:2px solid #e2e8f0;transition:all .3s ease}body.dark-mode .provider-response{background:#1e293b;border-color:#475569}.provider-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px;padding-bottom:12px;border-bottom:1px solid #e2e8f0}body.dark-mode .provider-header{border-bottom-color:#475569}.provider-name{font-weight:600;color:#1e293b;font-size:16px}body.dark-mode .provider-name{color:#f1f5f9}.loading-indicator{font-size:18px;animation:spin 1s linear infinite;color:#6366f1}.response-content{min-height:100px}.loading-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:20px}.typing-indicator{display:flex;gap:4px;margin-bottom:12px}.typing-indicator span{width:8px;height:8px;border-radius:50%;background:#6366f1;animation:typing 1.4s infinite ease-in-out}@keyframes typing{0%,80%,to{transform:scale(.7);opacity:.5}40%{transform:scale(1);opacity:1}}.error-state{text-align:center;padding:20px;color:#dc2626}.retry-btn{background:#dc2626;color:#fff;border:none;padding:8px 16px;border-radius:6px;font-size:12px;cursor:pointer;margin-top:8px}.response-text{font-size:14px;line-height:1.6;color:#374151}body.dark-mode .response-text{color:#d1d5db}.waiting-state{text-align:center;color:#6b7280;font-style:italic;padding:20px}.hint-section{background:linear-gradient(135deg,#fffbeb,#fef3c7);border:2px solid #f59e0b;border-radius:12px;padding:20px;margin-top:20px}body.dark-mode .hint-section{background:linear-gradient(135deg,#78350f,#92400e);border-color:#f59e0b}.hint-header{font-size:16px;font-weight:600;color:#92400e;margin-bottom:12px}body.dark-mode .hint-header{color:#fde68a}.hint-section p{color:#78350f;line-height:1.6}body.dark-mode .hint-section p{color:#fef3c7}.interactive-block{background:linear-gradient(135deg,#1e293b,#334155);border-radius:24px;padding:32px;margin:32px 0;color:#fff;position:relative;overflow:hidden;opacity:.5;pointer-events:none;transition:all .3s ease;box-shadow:0 8px 32px #0003;width:100%;box-sizing:border-box}@media (max-width: 768px){.interactive-block{padding:24px;margin:24px 0;border-radius:18px}}@media (max-width: 480px){.interactive-block{padding:20px;margin:16px 0;border-radius:16px}}.interactive-block.unlocked{opacity:1;pointer-events:auto}body.dark-mode .interactive-block{background:linear-gradient(135deg,#0f172a,#1e293b);box-shadow:0 8px 32px #0006}.interactive-block:before{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,transparent,rgba(255,255,255,.1),transparent);transition:left .5s}.interactive-block:hover:before{left:100%}.interactive-title{font-size:20px;font-weight:600;margin-bottom:15px;color:#f1f5f9}.prompt-input,.text-input{width:100%;background:#ffffff1a;border:2px solid rgba(255,255,255,.2);border-radius:12px;padding:15px;color:#fff;font-size:16px;margin:15px 0;resize:vertical;min-height:100px}.prompt-input::placeholder,.text-input::placeholder{color:#fff9}.api-buttons{display:flex;gap:12px;margin:24px 0;flex-wrap:wrap;justify-content:center}@media (max-width: 600px){.api-buttons{flex-direction:column;gap:8px}}.api-btn{background:linear-gradient(135deg,#6366f1,#8b5cf6);border:none;border-radius:12px;padding:14px 28px;color:#fff;font-weight:600;cursor:pointer;transition:all .3s ease;position:relative;overflow:hidden;font-size:14px;box-shadow:0 4px 16px #6366f14d}.api-btn:hover{transform:translateY(-2px);box-shadow:0 8px 24px #6366f166}.api-btn:active{transform:translateY(0)}.api-btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.response-area{background:#ffffff1a;border-radius:12px;padding:20px;margin-top:20px;min-height:150px;border:2px solid rgba(255,255,255,.2);font-family:SF Mono,Consolas,monospace;font-size:14px;line-height:1.6;white-space:pre-wrap}.csv-editor{background:#fffffff2;border-radius:12px;padding:20px;margin:20px 0;border:2px solid #e2e8f0}body.dark-mode .csv-editor{background:#1e293bf2;border-color:#475569}.csv-input{width:100%;height:200px;border:1px solid #d1d5db;border-radius:8px;padding:15px;font-family:SF Mono,Consolas,monospace;font-size:14px;resize:vertical;color:#1f2937}body.dark-mode .csv-input{background:#1e293b;border-color:#475569;color:#f1f5f9}body.dark-mode .csv-input::placeholder{color:#64748b}.file-upload{display:flex;flex-direction:column;align-items:center;justify-content:center;border:2px dashed rgba(255,255,255,.3);border-radius:12px;padding:30px;margin:20px 0;cursor:pointer;transition:all .3s ease;background:#ffffff0d}.file-upload:hover{border-color:#ffffff80;background:#ffffff1a}.file-upload input{display:none}.file-upload-text{font-size:16px;margin-bottom:10px}.file-upload-subtext{font-size:14px;opacity:.7}.implementation-guide{background:#ffffff0d;border-radius:16px;padding:24px;margin:20px 0;border:1px solid rgba(255,255,255,.1)}.implementation-guide h4{color:#f1f5f9;margin-bottom:20px;font-size:18px}.guide-steps{display:flex;flex-direction:column;gap:20px}.step{display:flex;gap:16px;align-items:flex-start}.step-number{background:linear-gradient(135deg,#6366f1,#8b5cf6);color:#fff;width:32px;height:32px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:600;flex-shrink:0}.step-content{flex:1}.step-content strong{color:#f1f5f9;display:block;margin-bottom:8px}.step-content p{color:#d1d5db;font-size:14px;line-height:1.5;margin:4px 0}.file-links{margin-top:8px}.file-link{display:inline-block;background:#6366f133;color:#818cf8;text-decoration:none;padding:8px 16px;border-radius:8px;font-weight:600;font-size:14px;margin-right:12px;transition:all .2s ease}.file-link:hover{background:#6366f14d;transform:translateY(-1px)}.file-desc{display:block;font-size:12px;color:#94a3b8;margin-top:4px}.copy-code-btn{background:#22c55e33;color:#4ade80;border:1px solid rgba(34,197,94,.3);padding:8px 16px;border-radius:8px;font-weight:600;font-size:14px;cursor:pointer;transition:all .2s ease}.copy-code-btn:hover{background:#22c55e4d;transform:translateY(-1px)}.code-preview{background:#0f172a;border-radius:8px;padding:16px;margin-top:12px;border:1px solid #334155;overflow-x:auto}.code-preview pre{margin:0;color:#e2e8f0;font-family:SF Mono,Consolas,monospace;font-size:12px;line-height:1.4}.demo-divider{text-align:center;margin:32px 0;position:relative}.demo-divider:before{content:"";position:absolute;top:50%;left:0;right:0;height:1px;background:#fff3}.demo-divider span{background:linear-gradient(135deg,#1e293b,#334155);padding:8px 20px;border-radius:20px;font-size:14px;font-weight:600;color:#94a3b8;position:relative}.sheets-demo{background:#fffffff2;border-radius:12px;margin:20px 0;overflow:hidden;border:2px solid #e2e8f0}body.dark-mode .sheets-demo{background:#1e293bf2;border-color:#475569}.sheets-header{background:#f8fafc;padding:12px 16px;border-bottom:1px solid #e2e8f0;display:flex;align-items:center;gap:12px}body.dark-mode .sheets-header{background:#1e293b;border-bottom-color:#475569}.sheet-tab{background:#fff;padding:8px 16px;border-radius:6px;font-weight:600;color:#374151;border:1px solid #d1d5db}body.dark-mode .sheet-tab{background:#334155;color:#f1f5f9;border-color:#475569}.sheets-btn{background:#6366f1;color:#fff;border:none;padding:8px 16px;border-radius:6px;font-size:12px;font-weight:600;cursor:pointer;transition:all .2s ease}.sheets-btn:hover{background:#5856eb;transform:translateY(-1px)}.sheets-grid{font-family:SF Mono,Consolas,monospace;font-size:12px}.grid-header,.grid-row{display:grid;grid-template-columns:80px 2fr 60px 1.5fr 1fr;border-bottom:1px solid #e2e8f0}body.dark-mode .grid-header,body.dark-mode .grid-row{border-bottom-color:#475569}.cell{padding:12px 8px;border-right:1px solid #e2e8f0;overflow:hidden;text-overflow:ellipsis;line-height:1.4}body.dark-mode .cell{border-right-color:#475569;color:#f1f5f9}.cell.header{background:#f1f5f9;font-weight:600;color:#374151}body.dark-mode .cell.header{background:#334155;color:#f1f5f9}.cell.ai-column{background:#fef3c7;color:#92400e}body.dark-mode .cell.ai-column{background:#451a03;color:#fcd34d}.cell.processing{font-style:italic;opacity:.7}.sheets-insights{padding:20px;background:#f8fafc;border-top:1px solid #e2e8f0}body.dark-mode .sheets-insights{background:#1e293b;border-top-color:#475569;color:#f1f5f9}.insight-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:16px;margin-top:16px}.insight-card{background:#fff;padding:16px;border-radius:8px;border:1px solid #e2e8f0}body.dark-mode .insight-card{background:#334155;border-color:#475569}.insight-card h5{margin-bottom:8px;color:#374151;font-size:14px}body.dark-mode .insight-card h5{color:#f1f5f9}.insight-card p{font-size:13px;line-height:1.5;color:#6b7280}body.dark-mode .insight-card p{color:#d1d5db}.lesson-navigation{display:flex;justify-content:space-between;align-items:center;margin-top:40px;padding-top:20px;border-top:1px solid #e2e8f0}.nav-btn{background:linear-gradient(135deg,#6366f1,#8b5cf6);border:none;border-radius:12px;padding:14px 28px;color:#fff;font-weight:600;cursor:pointer;transition:all .3s ease;font-size:14px;box-shadow:0 4px 16px #6366f14d}.nav-btn:hover{transform:translateY(-2px);box-shadow:0 8px 24px #6366f166}.nav-btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.next-lesson-btn{background:linear-gradient(135deg,#6366f1,#8b5cf6);border:none;border-radius:50px;padding:15px 40px;color:#fff;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;margin:30px auto;display:block;box-shadow:0 10px 25px #6366f14d}.next-lesson-btn:hover{transform:translateY(-3px);box-shadow:0 15px 35px #6366f166}.rich-text{margin:24px 0;line-height:1.7;color:#374151}.rich-text-default{background:#fffc;border-radius:12px;padding:20px;border-left:4px solid #e5e7eb}.rich-text-highlight{background:linear-gradient(135deg,#fff59d4d,#fef08a4d);border-radius:12px;padding:20px;border-left:4px solid #fbbf24;box-shadow:0 4px 12px #fbbf241a}.rich-text-callout{background:linear-gradient(135deg,#dbeafe80,#bfdbfe80);border-radius:12px;padding:20px;border-left:4px solid #3b82f6;box-shadow:0 4px 12px #3b82f61a}.rich-text-info{background:linear-gradient(135deg,#d1fae580,#a7f3d080);border-radius:12px;padding:20px;border-left:4px solid #10b981;box-shadow:0 4px 12px #10b9811a}.rich-text-warning{background:linear-gradient(135deg,#fef3c780,#fde68a80);border-radius:12px;padding:20px;border-left:4px solid #f59e0b;box-shadow:0 4px 12px #f59e0b1a}.rich-text-success{background:linear-gradient(135deg,#dcfce780,#bbf7d080);border-radius:12px;padding:20px;border-left:4px solid #059669;box-shadow:0 4px 12px #0596691a}.rich-text-h1{font-size:28px;font-weight:700;color:#1f2937;margin:0 0 16px;line-height:1.2}.rich-text-h2{font-size:24px;font-weight:600;color:#1f2937;margin:24px 0 14px;line-height:1.3}.rich-text-h3{font-size:20px;font-weight:600;color:#374151;margin:20px 0 12px;line-height:1.4}.rich-text-p{margin:0 0 16px;color:#4b5563;font-size:16px}.rich-text-p:last-child{margin-bottom:0}.rich-text-ul,.rich-text-ol{margin:16px 0;padding-left:24px;color:#4b5563}.rich-text-li{margin:8px 0;line-height:1.6}.rich-text-blockquote{margin:20px 0;padding:16px 20px;background:#00000008;border-left:4px solid #d1d5db;border-radius:0 8px 8px 0;font-style:italic;color:#6b7280}.rich-text-code{background:#0000000d;padding:2px 6px;border-radius:4px;font-family:SF Mono,Monaco,Cascadia Code,Roboto Mono,Consolas,Courier New,monospace;font-size:14px;color:#dc2626}.rich-text-pre{background:#0000000d;padding:16px;border-radius:8px;overflow-x:auto;margin:16px 0;border:1px solid rgba(0,0,0,.1)}.rich-text-pre code{background:none;padding:0;color:#374151;font-size:14px}.rich-text-strong{font-weight:600;color:#1f2937}.rich-text-em{font-style:italic}.rich-text-link{color:#3b82f6;text-decoration:underline;font-weight:500;transition:color .2s ease}.rich-text-link:hover{color:#1d4ed8;text-decoration:none}.sticky-progress-tracker{position:fixed;top:0;left:0;right:0;background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-bottom:1px solid rgba(255,255,255,.2);box-shadow:0 4px 20px #0000001a;z-index:1100;transform:translateY(-100%);transition:transform .3s ease,opacity .3s ease;opacity:0;padding:12px 20px}.sticky-progress-tracker.visible{transform:translateY(0);opacity:1}.progress-content{max-width:1200px;margin:0 auto;display:flex;flex-direction:column;gap:8px}.progress-main{display:flex;align-items:center;gap:20px}.lesson-info{display:flex;flex-direction:column;min-width:200px}.lesson-indicator{font-size:12px;font-weight:600;color:#6b7280;text-transform:uppercase;letter-spacing:.05em}.lesson-title-short{font-size:14px;font-weight:500;color:#1f2937;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:200px}.progress-bar-container{flex:1;position:relative}.sticky-progress-tracker .progress-bar{height:8px;background:#0000001a;border-radius:4px;overflow:hidden;position:relative}.sticky-progress-tracker .progress-fill{height:100%;background:linear-gradient(90deg,#6366f1,#8b5cf6);border-radius:4px;transition:width .5s ease;position:relative}.progress-text{position:absolute;right:8px;top:50%;transform:translateY(-50%);font-size:11px;font-weight:600;color:#4b5563}.progress-details{display:flex;align-items:center;justify-content:space-between;animation:slideDown .3s ease;background:#fffc;border-radius:8px;padding:8px 12px;margin-top:4px}.section-progress{display:flex;align-items:center;gap:8px}.progress-label{font-size:12px;color:#6b7280;font-weight:500}.progress-count{font-size:12px;color:#1f2937;font-weight:600}.progress-milestones{display:flex;gap:4px;align-items:center}.milestone{width:8px;height:8px;border-radius:50%;background:#0003;transition:all .3s ease}.milestone.completed{background:linear-gradient(135deg,#10b981,#059669);transform:scale(1.2);box-shadow:0 2px 4px #10b9814d}@keyframes slideDown{0%{opacity:0;transform:translateY(-10px)}to{opacity:1;transform:translateY(0)}}@media (max-width: 768px){.sticky-progress-tracker{padding:8px 16px}.progress-main{gap:12px}.lesson-info{min-width:120px}.lesson-title-short{max-width:120px;font-size:13px}.progress-details{flex-direction:column;align-items:flex-start;gap:8px}.progress-milestones{align-self:stretch;justify-content:center}}.header{padding:20px 0;border-bottom:1px solid rgba(255,255,255,.1);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);position:sticky;top:0;z-index:100}.header-content{max-width:1200px;margin:0 auto;padding:0 24px;display:flex;justify-content:space-between;align-items:center}.menu-btn{background:#ffffff1a;border:1px solid rgba(255,255,255,.2);color:#e2e8f0;padding:10px 16px;border-radius:12px;cursor:pointer;transition:all .3s ease;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px)}.menu-btn:hover{background:#ffffff26;transform:translateY(-2px)}.user-profile{display:flex;align-items:center;gap:8px;position:relative}.user-avatar{width:40px;height:40px;background:linear-gradient(135deg,#667eea,#764ba2);border-radius:50%;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:600;cursor:pointer;transition:all .3s ease}.user-avatar:hover{transform:scale(1.05);box-shadow:0 4px 12px #667eea4d}.dropdown-arrow{color:#94a3b8;cursor:pointer;transition:all .3s ease;-webkit-user-select:none;user-select:none}.dropdown-arrow:hover{color:#e2e8f0}.dropdown-arrow.open{transform:rotate(180deg)}.gamification-modal-overlay{position:fixed;top:0;left:0;width:100vw;height:100vh;background:#0006;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:1000;opacity:0;visibility:hidden;transition:all .3s ease}.gamification-modal-overlay.show{opacity:1;visibility:visible}.gamification-modal{position:absolute;top:70px;right:24px;width:320px;background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:16px;padding:24px;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);box-shadow:0 20px 40px #0000004d;transform:translateY(-10px);transition:all .3s ease}.gamification-modal.show{transform:translateY(0)}.gamification-modal:before{content:"";position:absolute;top:-6px;right:24px;width:12px;height:12px;background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-bottom:none;border-right:none;transform:rotate(45deg);-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px)}.gamification-panel{position:fixed;top:80px;right:20px;width:280px;background:#ffffff14;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:16px;box-shadow:0 20px 40px #0000004d,0 0 0 1px #ffffff1a inset,0 1px #fff3 inset;border:1px solid rgba(255,255,255,.15);z-index:850;animation:gamificationFloat 8s ease-in-out infinite;transition:all .3s cubic-bezier(.4,0,.2,1);overflow:hidden}@media (max-width: 1200px){.gamification-panel{width:260px;top:70px}}@media (max-width: 1024px){.gamification-panel{width:240px;top:60px}}@media (max-width: 768px){.gamification-panel{position:fixed;inset:auto 16px 16px;width:auto;margin-bottom:0;z-index:900;animation:none;max-width:none;border-radius:16px;box-shadow:0 8px 32px #00000026}.gamification-panel.collapsed{width:auto;border-radius:16px;left:auto;right:16px;width:fit-content;min-width:200px}.progress-indicator{justify-content:space-between;padding:12px 16px;gap:12px}.progress-ring{width:44px;height:44px}.progress-ring svg{width:44px;height:44px}.mobile-progress-text{display:flex;flex-direction:column;gap:2px}.points-mini{font-size:12px;font-weight:600}.streak-mini{font-size:11px}.expand-arrow{font-size:14px}.panel-content{padding:16px}.level-section{margin-bottom:16px}.level-badge{padding:6px 12px}.level-text{font-size:14px}.points-value{font-size:22px}.stats-grid{gap:10px;grid-template-columns:repeat(3,1fr)}.stat-item{padding:8px}.stat-value{font-size:16px}.stat-label{font-size:10px}.achievements-grid{gap:6px;grid-template-columns:repeat(2,1fr)}.achievement-item{padding:8px 6px}.achievement-name{font-size:10px}.achievement-popup{padding:16px}.achievement-popup-content{min-width:280px;max-width:calc(100vw - 32px);padding:20px}.mobile-progress-text{display:flex}}.gamification-panel.collapsed{width:auto;height:auto;border-radius:28px}@keyframes gamificationFloat{0%,to{transform:translateY(0)}50%{transform:translateY(-3px)}}.progress-indicator{display:flex;align-items:center;gap:8px;padding:8px 12px;cursor:pointer;transition:all .2s ease;border-radius:20px;background:#ffffff0d;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.1);box-shadow:0 4px 12px #0003,0 0 0 1px #ffffff0d inset}.progress-indicator:hover{background:#ffffff14;transform:translateY(-1px);box-shadow:0 6px 16px #00000040,0 0 0 1px #ffffff14 inset}.mobile-progress-text{display:none;flex-direction:column;align-items:flex-start;gap:2px}.points-mini{font-size:14px;font-weight:600;color:#1f2937}.streak-mini{font-size:12px;color:#6b7280}.progress-indicator:hover{background:#0000000d}.progress-ring{position:relative;width:48px;height:48px}.progress-ring-content{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);display:flex;align-items:center;justify-content:center}.level-mini{font-size:12px;font-weight:700;color:#1f2937}.expand-arrow{font-size:12px;color:#6b7280;transition:transform .3s ease}.gamification-panel.collapsed .expand-arrow{transform:rotate(180deg)}.panel-content{padding:20px;transition:all .3s cubic-bezier(.4,0,.2,1);background:#ffffff08;border-radius:12px;margin:8px;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.08)}.gamification-panel.collapsed .panel-content{max-height:0;padding:0;margin:0;opacity:0;transform:translateY(-10px);overflow:hidden;background:transparent;border:none;-webkit-backdrop-filter:none;backdrop-filter:none}.level-section{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}.level-badge{display:flex;align-items:center;gap:8px}.level-text{color:#fff;font-weight:600;font-size:14px}.level-icon{font-size:16px}.points-display{display:flex;flex-direction:column;align-items:flex-end}.points-value{font-size:24px;font-weight:700;color:#e2e8f0;line-height:1}.points-label{font-size:12px;color:#94a3b8;text-transform:uppercase;letter-spacing:.05em}.progress-to-next-level{margin-bottom:20px}.level-progress-bar{height:6px;background:#0000001a;border-radius:3px;overflow:hidden;margin-bottom:6px}.level-progress-fill{height:100%;background:linear-gradient(90deg,#fbbf24,#f59e0b);border-radius:3px;transition:width .5s ease}.next-level-text{font-size:11px;color:#6b7280}.stats-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-bottom:20px}.stat-item{display:flex;flex-direction:column;align-items:center;padding:12px 8px;background:#ffffff0f;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-radius:12px;text-align:center;border:1px solid rgba(255,255,255,.1);box-shadow:0 4px 12px #00000026,0 0 0 1px #ffffff0d inset;transition:all .3s ease}.stat-item:hover{background:#ffffff14;transform:translateY(-2px);box-shadow:0 6px 16px #0003,0 0 0 1px #ffffff14 inset}.stat-icon{font-size:20px;margin-bottom:4px}.stat-value{font-size:18px;font-weight:700;color:#e2e8f0;line-height:1}.stat-label{font-size:11px;color:#94a3b8;text-transform:uppercase;letter-spacing:.05em}.achievements-section{border-top:1px solid rgba(0,0,0,.1);padding-top:16px}.achievements-title{font-size:14px;font-weight:600;color:#e2e8f0;margin-bottom:12px}.achievements-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:8px}.achievement-item{display:flex;flex-direction:column;align-items:center;padding:10px 8px;background:#ffffff0f;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-radius:12px;text-align:center;transition:all .3s ease;cursor:help;border:1px solid rgba(255,255,255,.1);box-shadow:0 4px 12px #00000026,0 0 0 1px #ffffff0d inset}.achievement-item:hover{background:#ffffff14;transform:translateY(-2px);box-shadow:0 6px 16px #0003,0 0 0 1px #ffffff14 inset}.achievement-item.unlocked{background:#22c55e1a;border-color:#22c55e4d;box-shadow:0 4px 12px #22c55e33,0 0 0 1px #22c55e1a inset}.achievement-item.locked{opacity:.5;background:#ffffff08;filter:grayscale(100%)}.achievement-icon{font-size:16px;margin-bottom:4px}.achievement-name{font-size:10px;font-weight:500;color:#d1d5db;line-height:1.2}.achievement-popup{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%);z-index:1500;animation:achievementAppear .5s ease}@keyframes achievementAppear{0%{opacity:0;transform:translate(-50%,-50%) scale(.8)}to{opacity:1;transform:translate(-50%,-50%) scale(1)}}.achievement-popup-content{background:linear-gradient(135deg,#fbbf24,#f59e0b);color:#fff;padding:24px;border-radius:16px;box-shadow:0 20px 40px #fbbf244d;text-align:center;min-width:300px}.achievement-popup-icon{font-size:40px;margin-bottom:12px}.achievement-details h3{font-size:20px;font-weight:700;margin-bottom:12px}.new-achievement{display:flex;align-items:center;justify-content:center;gap:8px;margin-bottom:8px}.new-achievement-icon{font-size:24px}.new-achievement-name{font-size:18px;font-weight:600}.achievement-description{font-size:14px;margin-bottom:8px;opacity:.9}.points-earned{font-size:16px;font-weight:700}@media (max-width: 480px){.nav-popover{min-width:280px;max-width:calc(100vw - 24px);max-height:65vh}.nav-popover-content{padding:12px;max-height:65vh}.gamification-panel.collapsed{min-width:180px}.progress-indicator{padding:10px 14px}.mobile-progress-text{gap:1px}.points-mini{font-size:11px}.streak-mini{font-size:10px}.panel-content{padding:14px}.stats-grid{gap:8px}.stat-item{padding:6px}.achievement-popup-content{min-width:260px;padding:20px}}.next-lesson-btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.loading{display:inline-block;width:20px;height:20px;border:3px solid rgba(255,255,255,.3);border-radius:50%;border-top-color:#fff;animation:spin 1s ease-in-out infinite}@keyframes spin{to{transform:rotate(360deg)}}.fade-in{animation:fadeIn .6s ease-out}@keyframes fadeIn{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.review-block{background:linear-gradient(135deg,#f0f9ff,#e0f2fe);border:2px solid #0ea5e9;border-radius:20px;padding:32px;margin:32px 0;transition:all .3s ease;opacity:.5;pointer-events:none}.review-block.unlocked{opacity:1;pointer-events:auto}.review-block.completed{border-color:#10b981;background:linear-gradient(135deg,#ecfdf5,#d1fae5)}.review-header{margin-bottom:24px;text-align:center}.review-title{font-size:24px;font-weight:700;color:#0c4a6e;margin-bottom:12px;display:flex;align-items:center;justify-content:center;gap:8px}.review-description{color:#0369a1;font-size:16px;line-height:1.6;margin-bottom:20px}.review-summary{background:#ffffffb3;border-radius:12px;padding:20px;margin-top:16px}.summary-text{font-weight:600;color:#0c4a6e;margin-bottom:12px}.review-stats{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}.stat-item{background:#0ea5e91a;color:#0369a1;padding:6px 12px;border-radius:16px;font-size:14px;font-weight:500}.review-start{text-align:center;padding:40px 20px}.start-instructions{margin-bottom:24px}.start-instructions p{font-size:16px;color:#0369a1;line-height:1.6;margin-bottom:20px}.topics-preview{background:#fffc;border-radius:12px;padding:20px;text-align:left;max-width:400px;margin:0 auto}.topics-preview ul{margin:12px 0 0 20px;color:#0369a1}.topics-preview li{margin-bottom:8px}.start-review-btn{background:linear-gradient(135deg,#0ea5e9,#0284c7);color:#fff;border:none;border-radius:12px;padding:16px 32px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;box-shadow:0 4px 16px #0ea5e94d}.start-review-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 8px 24px #0ea5e966}.start-review-btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.provider-warning{color:#dc2626;font-size:14px;margin-top:12px;font-style:italic}.review-chat{max-height:600px;display:flex;flex-direction:column}.chat-messages{flex:1;max-height:400px;overflow-y:auto;padding:20px 0;display:flex;flex-direction:column;gap:16px}.chat-message{display:flex;gap:12px;align-items:flex-start}.chat-message.user{flex-direction:row-reverse}.message-avatar{width:36px;height:36px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;flex-shrink:0}.chat-message.user .message-avatar{background:#0ea5e9}.chat-message.assistant .message-avatar{background:#10b981}.message-content{flex:1;max-width:80%}.chat-message.user .message-content{text-align:right}.message-text{background:#fff;padding:16px;border-radius:16px;box-shadow:0 2px 8px #0000001a;line-height:1.6;color:#374151}.chat-message.user .message-text{background:#eff6ff;border:1px solid #bfdbfe}.message-timestamp{font-size:12px;color:#6b7280;margin-top:4px}.typing-indicator{display:flex;gap:4px;padding:16px}.typing-indicator span{width:8px;height:8px;border-radius:50%;background:#10b981;animation:typing 1.4s infinite ease-in-out}.typing-indicator span:nth-child(1){animation-delay:-.32s}.typing-indicator span:nth-child(2){animation-delay:-.16s}.chat-input-container{border-top:1px solid #e5e7eb;padding-top:16px;margin-top:16px}.progress-indicator{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px;font-size:14px;color:#6b7280}.completion-badge{color:#10b981;font-weight:600}.chat-input-wrapper{display:flex;gap:12px;align-items:flex-end}.chat-input{flex:1;resize:vertical;border:2px solid #e5e7eb;border-radius:12px;padding:12px 16px;font-size:14px;line-height:1.5;font-family:inherit;max-height:120px;min-height:44px}.chat-input:focus{outline:none;border-color:#0ea5e9}.chat-input:disabled{opacity:.6;cursor:not-allowed}.send-button{background:#0ea5e9;color:#fff;border:none;border-radius:10px;width:44px;height:44px;display:flex;align-items:center;justify-content:center;cursor:pointer;transition:all .2s ease;font-size:16px}.send-button:hover:not(:disabled){background:#0284c7;transform:translateY(-1px)}.send-button:disabled{opacity:.5;cursor:not-allowed;transform:none}body.dark-mode .review-block{background:linear-gradient(135deg,#1e293b,#334155);border-color:#0ea5e9}body.dark-mode .review-block.completed{border-color:#10b981;background:linear-gradient(135deg,#064e3b,#065f46)}body.dark-mode .review-title{color:#38bdf8}body.dark-mode .review-description{color:#bae6fd}body.dark-mode .review-summary{background:#1e293bcc}body.dark-mode .summary-text{color:#38bdf8}body.dark-mode .stat-item{background:#0ea5e933;color:#bae6fd}body.dark-mode .topics-preview{background:#1e293bcc;color:#bae6fd}body.dark-mode .message-text{background:#374151;color:#f3f4f6}body.dark-mode .chat-message.user .message-text{background:#1e40af;border-color:#3b82f6;color:#fff}body.dark-mode .chat-input{background:#374151;border-color:#4b5563;color:#f3f4f6}body.dark-mode .chat-input:focus{border-color:#0ea5e9}@media (max-width: 768px){.review-block{padding:24px;margin:24px 0}.review-stats{gap:8px}.stat-item{font-size:12px;padding:4px 8px}.message-content{max-width:85%}.topics-preview{padding:16px}}@media (max-width: 480px){.review-block{padding:20px;border-radius:16px}.review-title{font-size:20px}.review-stats{flex-direction:column;align-items:center}.chat-messages{max-height:300px}.message-content{max-width:90%}.chat-input-wrapper{flex-direction:column;gap:8px}.send-button{align-self:flex-end}}body.dark-mode{background:linear-gradient(135deg,#1e293b,#0f172a)}.floating-navigation{position:fixed;top:20px;left:20px;z-index:1002}.nav-tab{display:flex;align-items:center;background:#fff;border:1px solid #e5e7eb;border-radius:16px;padding:12px 20px;color:#1f2937;font-weight:600;cursor:pointer;transition:all .3s cubic-bezier(.4,0,.2,1);box-shadow:0 8px 32px #0000001a;min-width:100px}.nav-tab:hover{background:#f9fafb;transform:translateY(-2px);box-shadow:0 12px 40px #00000026}.nav-tab.open{background:#f3f4f6;border-color:#d1d5db}.nav-tab-content{display:flex;align-items:center;gap:8px}.nav-icon{font-size:16px;transition:transform .3s ease}.nav-tab.open .nav-icon{transform:rotate(180deg)}.nav-text{font-size:14px}.nav-popover{position:absolute;top:70px;left:0;min-width:400px;max-width:450px;max-height:80vh;background:#fff;border:1px solid #e5e7eb;border-radius:20px;box-shadow:0 20px 60px #00000026;opacity:0;visibility:hidden;transform:translateY(-20px) scale(.95);transition:all .3s cubic-bezier(.4,0,.2,1);overflow:hidden;z-index:1003}.nav-popover.open{opacity:1;visibility:visible;transform:translateY(0) scale(1)}.nav-popover-content{padding:24px;max-height:80vh;overflow-y:auto;overflow-x:hidden}.nav-section{margin-bottom:24px}.nav-section:last-child{margin-bottom:0}.quick-nav{margin-bottom:20px}.home-button{display:flex;align-items:center;gap:10px;width:100%;padding:12px 16px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;text-decoration:none;border-radius:12px;font-weight:600;transition:all .3s ease;box-shadow:0 2px 8px #667eea33}.home-button:hover{transform:translateY(-2px);box-shadow:0 4px 12px #667eea4d}.home-icon{font-size:1.2rem}.section-header{display:flex;align-items:center;gap:8px;margin-bottom:16px}.section-icon{font-size:18px}.section-header h3{font-size:16px;font-weight:600;color:#1f2937;margin:0}.progress-section .progress-info{display:flex;flex-direction:column;gap:8px}.progress-bar-container{width:100%;height:8px;background:#ffffff1a;border-radius:4px;overflow:hidden}.progress-bar-fill{height:100%;background:linear-gradient(90deg,#10b981,#3b82f6);border-radius:4px;transition:width .5s ease}.progress-text{font-size:12px;color:#6b7280;text-align:center}.lessons-grid{display:flex;flex-direction:column;gap:8px}.lesson-item{display:flex;align-items:center;padding:12px 16px;background:#6366f10d;border:1px solid rgba(99,102,241,.1);border-radius:12px;cursor:pointer;transition:all .2s ease;text-align:left;color:#1f2937}.lesson-item:hover:not(.locked){background:#6366f11a;transform:translate(4px)}.lesson-item.active{background:#6366f14d;border-color:#6366f180;box-shadow:0 0 20px #6366f133}.lesson-item.completed .lesson-number{background:#10b981;color:#fff}.lesson-item.locked{opacity:.5;cursor:not-allowed}.lesson-item .lesson-number{display:flex;align-items:center;justify-content:center;width:32px;height:32px;background:#ffffff1a;border-radius:8px;font-weight:600;font-size:14px;margin-right:12px;flex-shrink:0;padding:0;letter-spacing:normal;text-transform:none;color:inherit;border:none}.lesson-info{flex:1;min-width:0}.lesson-title{font-weight:600;font-size:14px;margin-bottom:2px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.lesson-category{font-size:12px;color:#6b7280;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.lesson-lock{font-size:14px;opacity:.7;margin-left:8px}.account-info{color:#1f2937}.user-info{display:flex;align-items:center;justify-content:space-between;gap:12px}.user-details{flex:1;min-width:0}.user-email{font-weight:600;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.user-status{font-size:12px;color:#6b7280}.auth-prompt{text-align:center}.auth-prompt p{font-size:12px;color:#6b7280;margin-bottom:12px}.auth-button{padding:8px 16px;border:1px solid rgba(255,255,255,.2);border-radius:8px;font-size:12px;font-weight:600;cursor:pointer;transition:all .2s ease}.auth-button.signin{background:#6366f1e6;color:#fff;width:100%}.auth-button.signin:hover{background:#6366f14d}.auth-button.logout{background:#ef4444e6;color:#fff}.auth-button.logout:hover{background:#ef44444d}.nav-backdrop{position:fixed;inset:0;background:#0003;backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);z-index:1001;animation:fadeIn .3s ease}body.dark-mode .nav-tab{background:#1e293b;border-color:#374151;color:#f1f5f9}body.dark-mode .nav-tab:hover{background:#334155}body.dark-mode .nav-tab.open{background:#374151;border-color:#4b5563}body.dark-mode .nav-popover{background:#1e293b;border-color:#374151}body.dark-mode .lesson-item{background:#0003;border-color:#ffffff0d}body.dark-mode .lesson-item:hover:not(.locked){background:#0000004d}body.dark-mode .section-header h3{color:#f1f5f9}body.dark-mode .progress-text,body.dark-mode .lesson-category{color:#94a3b8}body.dark-mode .account-info{color:#f1f5f9}body.dark-mode .user-status,body.dark-mode .auth-prompt p{color:#94a3b8}@media (max-width: 768px){.floating-navigation{top:16px;left:16px}.nav-tab{padding:10px 16px;border-radius:12px;box-shadow:0 4px 20px #00000026}.nav-tab-content{gap:8px}.nav-icon{font-size:16px}.nav-text{font-size:14px;font-weight:500}.nav-popover{min-width:320px;max-width:calc(100vw - 32px);max-height:70vh;box-shadow:0 8px 40px #0003;border-radius:16px}.nav-popover-content{padding:16px;max-height:70vh}.section-header{margin-bottom:12px}.section-header h3{font-size:16px}.lesson-item{padding:12px;border-radius:10px}.lesson-title{font-size:13px}.lesson-category{font-size:11px}.setting-btn{padding:10px 14px;font-size:13px}.setting-icon{font-size:14px}}.nav-popover-content::-webkit-scrollbar{width:6px}.nav-popover-content::-webkit-scrollbar-track{background:transparent}.nav-popover-content::-webkit-scrollbar-thumb{background:#d1d5db;border-radius:3px}.nav-popover-content::-webkit-scrollbar-thumb:hover{background:#9ca3af}body.dark-mode .nav-popover-content::-webkit-scrollbar-thumb{background:#4b5563}body.dark-mode .nav-popover-content::-webkit-scrollbar-thumb:hover{background:#6b7280}.modal-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px}.modal-title{color:#e2e8f0;font-size:1.1rem;font-weight:600;margin:0}.modal-close{background:none;border:none;color:#94a3b8;font-size:1.2rem;cursor:pointer;padding:4px;border-radius:4px;transition:all .3s ease}.modal-close:hover{color:#e2e8f0;background:#ffffff1a}.level-badge{background:linear-gradient(135deg,#f59e0b,#d97706);color:#fff;padding:6px 12px;border-radius:12px;font-size:.8rem;font-weight:600;display:inline-flex;align-items:center;gap:4px;margin-bottom:8px}.points-display{font-size:2rem;font-weight:700;color:#e2e8f0;margin-bottom:4px}.points-label{color:#94a3b8;font-size:.8rem;text-transform:uppercase;letter-spacing:.5px}.progress-text{color:#64748b;font-size:.85rem;margin-top:12px}.stats-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:20px 0}.stat-item{text-align:center;padding:16px 8px;background:#ffffff08;border-radius:12px}.stat-number{font-size:1.5rem;font-weight:700;color:#e2e8f0;margin-bottom:4px}.stat-label{color:#64748b;font-size:.7rem;text-transform:uppercase;letter-spacing:.5px}.achievements-section{margin-top:24px}.achievements-title{font-size:1.1rem;font-weight:600;margin-bottom:16px;color:#e2e8f0}.achievements-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.achievement-badge{background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:12px;padding:12px;text-align:center;transition:all .3s ease}.achievement-badge:hover{transform:translateY(-2px);background:#ffffff1a}.achievement-icon{font-size:1.5rem;margin-bottom:4px}.achievement-label{font-size:.7rem;color:#94a3b8}.main-content{padding:40px 0}.content-grid{display:grid;grid-template-columns:1fr;gap:32px;margin-top:40px}.main-column{width:100%;max-width:800px;margin:0 auto}.course-header{text-align:center;margin-bottom:48px}.course-badge{display:inline-block;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:8px 20px;border-radius:20px;font-size:14px;font-weight:600;letter-spacing:.5px;margin-bottom:16px;text-transform:uppercase}.course-title{font-size:2.5rem;font-weight:700;margin-bottom:16px;background:linear-gradient(135deg,#e2e8f0,#94a3b8);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.course-description{font-size:1.2rem;color:#94a3b8;max-width:600px;margin:0 auto}@media (max-width: 1024px){.gamification-modal{width:280px}.container{padding:24px 16px}}@media (max-width: 768px){.gamification-modal{width:calc(100vw - 32px);right:16px;left:16px;margin:0 auto}.stats-grid{grid-template-columns:repeat(3,1fr);gap:12px}.container{padding:16px 16px 120px}.course-title{font-size:2rem}.header-content{padding:0 16px}}@media (max-width: 480px){.container{padding:12px 12px 120px}.course-title{font-size:1.75rem}.header-content{padding:0 12px}}.welcome-splash{position:fixed;top:0;left:0;width:100%;height:100vh;z-index:1000;overflow:hidden}.skyline-container{position:relative;width:100%;height:100%;display:flex;align-items:center;justify-content:center}.sky-background{position:absolute;top:0;left:0;width:100%;height:100%;transition:background 1s ease-in-out}.sky-background.day{background:linear-gradient(180deg,#87ceeb,#667eea,#764ba2)}.sky-background.night{background:linear-gradient(180deg,#0f172a,#1e293b 30%,#334155 70%,#475569)}.cloud{position:absolute;background:#fffc;border-radius:50px;animation:floatClouds 20s ease-in-out infinite}.cloud:before,.cloud:after{content:"";position:absolute;background:#fffc;border-radius:50px}.cloud-1{width:80px;height:35px;top:15%;left:20%;animation-delay:0s}.cloud-1:before{width:50px;height:50px;top:-25px;left:10px}.cloud-1:after{width:60px;height:40px;top:-15px;right:10px}.cloud-2{width:60px;height:25px;top:25%;right:25%;animation-delay:-5s}.cloud-2:before{width:35px;height:35px;top:-18px;left:8px}.cloud-2:after{width:45px;height:30px;top:-12px;right:8px}.cloud-3{width:100px;height:40px;top:10%;left:60%;animation-delay:-10s}.cloud-3:before{width:60px;height:60px;top:-30px;left:15px}.cloud-3:after{width:70px;height:45px;top:-20px;right:15px}.cloud-4{width:70px;height:30px;top:30%;left:10%;animation-delay:-15s}.cloud-4:before{width:40px;height:40px;top:-20px;left:10px}.cloud-4:after{width:50px;height:35px;top:-15px;right:10px}@keyframes floatClouds{0%,to{transform:translate(0) translateY(0)}25%{transform:translate(10px) translateY(-5px)}50%{transform:translate(-5px) translateY(3px)}75%{transform:translate(8px) translateY(-2px)}}.stars{position:absolute;top:0;left:0;width:100%;height:70%}.star{position:absolute;background:#fff;border-radius:50%;animation:twinkle 3s ease-in-out infinite}.star-1{width:2px;height:2px;top:20%;left:15%;animation-delay:0s}.star-2{width:3px;height:3px;top:30%;left:70%;animation-delay:1s}.star-3{width:2px;height:2px;top:15%;left:45%;animation-delay:2s}.star-4{width:1px;height:1px;top:25%;left:85%;animation-delay:.5s}.star-5{width:2px;height:2px;top:10%;left:30%;animation-delay:1.5s}.star-6{width:1px;height:1px;top:35%;left:60%;animation-delay:2.5s}@keyframes twinkle{0%,to{opacity:.3;transform:scale(1)}50%{opacity:1;transform:scale(1.2)}}.skyline{position:absolute;bottom:0;left:0;width:100%;height:30%;display:flex;align-items:flex-end;justify-content:space-between;padding:0 5%}.building{background:linear-gradient(180deg,#1e293be6,#1e293b);position:relative;margin:0 2px}.building-1{width:60px;height:120px}.building-2{width:80px;height:160px}.building-3{width:50px;height:100px}.building-4{width:90px;height:200px}.building-5{width:70px;height:140px}.building-6{width:55px;height:110px}.building-7{width:75px;height:180px}.building:before{content:"";position:absolute;width:4px;height:4px;background:#fbbf24;border-radius:50%;top:20%;left:20%;box-shadow:15px 0 #fbbf24,0 15px #fbbf24,15px 15px #fbbf24,0 30px #fbbf24,15px 30px #fbbf24}.welcome-content{position:relative;z-index:10;max-width:500px;margin:0 auto;padding:40px;text-align:center;background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:24px;box-shadow:0 20px 40px #00000026;border:1px solid rgba(255,255,255,.2)}.welcome-title{font-size:32px;font-weight:700;color:#1f2937;margin-bottom:12px;background:linear-gradient(135deg,#667eea,#764ba2);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.welcome-subtitle{font-size:16px;color:#6b7280;margin-bottom:32px;line-height:1.5}.welcome-error{background:#fef2f2;border:1px solid #fecaca;color:#991b1b;padding:12px 16px;border-radius:8px;margin-bottom:20px;font-size:14px}.welcome-form{margin-bottom:32px}.api-input-container{margin-bottom:24px}.input-wrapper{position:relative;display:flex;align-items:center;background:#fff;border:2px solid #e2e8f0;border-radius:12px;padding:4px;transition:all .3s ease}.input-wrapper:focus-within{border-color:#667eea;box-shadow:0 0 0 3px #667eea1a}.welcome-api-input{flex:1;padding:16px 20px;border:none;outline:none;font-size:16px;background:transparent;color:#1f2937}.welcome-api-input::placeholder{color:#9ca3af}.toggle-visibility-btn{background:none;border:none;padding:12px;cursor:pointer;font-size:18px;border-radius:8px;transition:background-color .2s ease}.toggle-visibility-btn:hover{background:#f3f4f6}.provider-detected{margin-top:12px;text-align:left}.provider-badge{display:inline-block;background:linear-gradient(135deg,#ecfdf5,#d1fae5);color:#059669;padding:6px 12px;border-radius:20px;font-size:12px;font-weight:600;border:1px solid #a7f3d0}.welcome-submit-btn{width:100%;padding:16px 24px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:12px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;justify-content:center;gap:8px}.welcome-submit-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 12px 25px #667eea4d}.welcome-submit-btn:disabled{opacity:.6;cursor:not-allowed;transform:none}.spinner{width:16px;height:16px;border:2px solid rgba(255,255,255,.3);border-top-color:#fff;border-radius:50%;animation:spin 1s linear infinite}.api-key-help{background:#f9fafb;border-radius:12px;padding:24px;text-align:left}.api-key-help h4{font-size:16px;font-weight:600;color:#374151;margin-bottom:16px}.api-key-help ul{list-style:none;margin-bottom:16px}.api-key-help li{padding:8px 0;color:#4b5563;font-size:14px;border-bottom:1px solid #e5e7eb}.api-key-help li:last-child{border-bottom:none}.api-key-help strong{color:#1f2937;font-weight:600}.privacy-note{font-size:13px;color:#6b7280;font-style:italic;text-align:center;margin:24px 0 0;padding:16px;background:#f9fafb;border-radius:8px;border:1px solid #e5e7eb}@media (max-width: 640px){.welcome-content{margin:20px;padding:24px}.welcome-title{font-size:24px}.skyline{height:25%}.building{margin:0 1px}.cloud{transform:scale(.8)}}