:root{--green-50:#f0fdf4;--green-100:#dcfce7;--green-200:#bbf7d0;--green-400:#4ade80;--green-500:#22c55e;--green-600:#16a34a;--green-700:#15803d;--green-800:#166534;--gray-50:#f9fafb;--gray-100:#f3f4f6;--gray-200:#e5e7eb;--gray-300:#d1d5db;--gray-400:#9ca3af;--gray-500:#6b7280;--gray-600:#4b5563;--gray-700:#374151;--gray-800:#1f2937;--gray-900:#111827;--radius-sm:10px;--radius-md:16px;--radius-lg:24px;--radius-full:9999px;--shadow-card:0 2px 8px #0000000f, 0 0 1px #0000001a;--shadow-lg:0 8px 24px #0000001a, 0 0 1px #0000001a}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--gray-50);color:var(--gray-800);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-family:-apple-system,BlinkMacSystemFont,SF Pro Display,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.5}.app-container{max-width:480px;min-height:100vh;margin:0 auto;padding:0 16px}.app-bar{border-bottom:1px solid 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22px}.step-subtitle{color:var(--gray-500);text-align:center;margin-bottom:24px;font-size:.95rem;line-height:1.5}.step-hint{text-align:center;color:var(--gray-400);margin-top:12px;font-size:.8rem}.btn-primary{background:var(--green-500);color:#fff;border-radius:var(--radius-full);cursor:pointer;-webkit-tap-highlight-color:transparent;border:none;justify-content:center;align-items:center;gap:10px;width:100%;padding:14px 28px;font-size:1.05rem;font-weight:600;transition:background .15s,transform .1s;display:inline-flex}.btn-primary:hover{background:var(--green-600)}.btn-primary:active{transform:scale(.97)}.btn-primary:disabled{background:var(--gray-300);cursor:not-allowed}.btn-large{padding:18px 32px;font-size:1.15rem}.scanner-cta-card{text-align:center;padding:36px 22px 28px}.scanner-icon-wrap{margin-bottom:20px}.scanner-big-icon{width:80px;height:80px}.scanner-cta-card h1{color:var(--gray-900);margin-bottom:10px;font-size:1.6rem;font-weight:800;line-height:1.2}.viewfinder-card{padding:16px}.viewfinder{border-radius:var(--radius-md);margin-bottom:16px;position:relative;overflow:hidden}.viewfinder-screen{aspect-ratio:3/4;border-radius:var(--radius-md);background:#0a0a0a;width:100%;position:relative;overflow:hidden}.vf-corner{border-color:var(--green-400);z-index:2;border-style:solid;border-width:0;width:36px;height:36px;position:absolute}.vf-tl{border-top-width:3px;border-left-width:3px;border-radius:4px 0 0;top:16px;left:16px}.vf-tr{border-top-width:3px;border-right-width:3px;border-radius:0 4px 0 0;top:16px;right:16px}.vf-bl{border-bottom-width:3px;border-left-width:3px;border-radius:0 0 0 4px;bottom:16px;left:16px}.vf-br{border-bottom-width:3px;border-right-width:3px;border-radius:0 0 4px;bottom:16px;right:16px}.scan-line{background:var(--green-400);z-index:3;height:2px;animation:2.5s ease-in-out infinite scanMove;position:absolute;left:16px;right:16px;box-shadow:0 0 12px 3px #4ade8073}@keyframes scanMove{0%{top:16px}50%{top:calc(100% - 18px)}to{top:16px}}.vf-grid{z-index:1;position:absolute;inset:16px}.vf-grid-line{background:#ffffff0f;position:absolute}.vf-h1{height:1px;top:33.3%;left:0;right:0}.vf-h2{height:1px;top:66.6%;left:0;right:0}.vf-v1{width:1px;top:0;bottom:0;left:33.3%}.vf-v2{width:1px;top:0;bottom:0;left:66.6%}.vf-label{color:var(--green-400);letter-spacing:3px;z-index:4;font-size:.7rem;font-weight:700;animation:1.5s ease-in-out infinite pulse;position:absolute;top:28px;left:50%;transform:translate(-50%)}@keyframes pulse{0%,to{opacity:1}50%{opacity:.4}}.vf-dots{z-index:4;gap:6px;display:flex;position:absolute;bottom:28px;left:50%;transform:translate(-50%)}.vf-dots span{background:var(--green-400);border-radius:50%;width:6px;height:6px;animation:1.2s ease-in-out infinite dotPulse}.vf-dots span:nth-child(2){animation-delay:.2s}.vf-dots span:nth-child(3){animation-delay:.4s}@keyframes dotPulse{0%,to{opacity:.3;transform:scale(.8)}50%{opacity:1;transform:scale(1.2)}}.vf-status{text-align:center;color:var(--gray-600);margin-bottom:12px;font-size:.95rem;font-weight:500}.vf-progress-wrap{background:var(--gray-200);border-radius:var(--radius-full);height:6px;overflow:hidden}.vf-progress-bar{background:linear-gradient(90deg, var(--green-400), var(--green-600));border-radius:var(--radius-full);width:0%;height:100%;transition:width .1s linear}.analyzing-card{text-align:center;padding:40px 22px}.analyzing-spinner{border:4px solid var(--green-200);border-top-color:var(--green-500);border-radius:50%;width:48px;height:48px;margin:0 auto 20px;animation:.8s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}.analyzing-card h2{color:var(--gray-800);margin-bottom:20px;font-size:1.25rem}.detect-info{margin-bottom:20px}.detect-badge{background:var(--green-50);color:var(--green-700);border-radius:var(--radius-sm);align-items:center;gap:8px;margin-bottom:8px;padding:10px 16px;font-size:.9rem;font-weight:600;animation:.3s ease-out fadeUp;display:flex}.detect-badge-secondary{background:var(--gray-100);color:var(--gray-700)}.analyze-progress-wrap{background:var(--gray-200);border-radius:var(--radius-full);height:8px;margin-bottom:12px;overflow:hidden}.analyze-progress-bar{background:linear-gradient(90deg, var(--green-400), var(--green-600));border-radius:var(--radius-full);width:0%;height:100%;transition:width .1s linear}.analyze-sub{color:var(--gray-500);font-size:.85rem}.results-card{padding:24px 18px}.results-header{text-align:center;margin-bottom:24px}.results-check{background:var(--green-50);border-radius:50%;justify-content:center;align-items:center;width:56px;height:56px;margin:0 auto 14px;display:flex}.results-header h2{color:var(--gray-900);margin-bottom:6px;font-size:1.2rem}.results-sub{color:var(--gray-500);font-size:.9rem}.answers-list{margin-bottom:20px}.answer-item{background:var(--gray-50);border-radius:var(--radius-sm);align-items:flex-start;gap:12px;margin-bottom:8px;padding:14px;display:flex;position:relative}.answer-item.answer-locked{background:var(--gray-100)}.answer-num{background:var(--green-500);color:#fff;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:28px;height:28px;font-size:.8rem;font-weight:700;display:flex}.answer-locked .answer-num{background:var(--gray-300)}.answer-body{flex:1;min-width:0}.answer-blurred{filter:blur(5px);-webkit-user-select:none;user-select:none;pointer-events:none}.answer-question{color:var(--gray-600);margin-bottom:4px;font-size:.85rem}.answer-value{color:var(--gray-900);margin-bottom:4px;font-size:1rem;font-weight:700}.answer-steps{color:var(--gray-500);font-size:.8rem;line-height:1.4}.lock-icon{color:var(--gray-400);flex-shrink:0;align-self:center}.gate-card{background:var(--green-50);border:2px solid var(--green-200);border-radius:var(--radius-md);text-align:center;padding:24px 20px}.gate-card h3{color:var(--green-800);margin-bottom:6px;font-size:1.1rem}.gate-card p{color:var(--gray-600);margin-bottom:16px;font-size:.9rem}.gate-form{flex-direction:column;gap:10px;display:flex}.gate-form input[type=email]{border:2px solid var(--gray-200);border-radius:var(--radius-sm);outline:none;width:100%;padding:14px 16px;font-family:inherit;font-size:1rem;transition:border-color .15s}.gate-form input[type=email]:focus{border-color:var(--green-400)}.textbook-card{text-align:center;padding:32px 22px}.textbook-card h2{color:var(--gray-900);margin-bottom:8px;font-size:1.25rem}.textbook-select-wrap{flex-direction:column;gap:12px;margin-top:24px;display:flex}.textbook-select{border:2px solid var(--gray-200);border-radius:var(--radius-sm);color:var(--gray-800);appearance:none;cursor:pointer;background:#fff url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='%236b7280' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E") right 14px center no-repeat;outline:none;padding:14px 16px;font-family:inherit;font-size:1rem}.textbook-select:focus{border-color:var(--green-400)}.final-card{padding:24px 18px}.final-header{text-align:center;margin-bottom:24px}.final-header svg{margin-bottom:8px}.final-header h2{color:var(--gray-900);margin-bottom:6px;font-size:1.2rem}.final-textbook{color:var(--green-600);font-size:.85rem;font-weight:600}.answer-full-item{border:1px solid var(--gray-200);background:#fff}.confidence-bar-wrap{align-items:center;gap:8px;margin-top:8px;display:flex}.confidence-label{color:var(--gray-400);flex-shrink:0;font-size:.75rem}.confidence-track{background:var(--gray-200);border-radius:var(--radius-full);flex:1;height:5px;overflow:hidden}.confidence-fill{background:var(--green-500);border-radius:var(--radius-full);height:100%}.confidence-pct{color:var(--green-600);text-align:right;flex-shrink:0;min-width:32px;font-size:.75rem;font-weight:700}.final-actions{text-align:center;margin-top:20px}.features-section{margin-top:40px;margin-bottom:40px}.features-section h2{text-align:center;color:var(--gray-900);margin-bottom:20px;font-size:1.4rem}.features-grid{grid-template-columns:1fr;gap:12px;display:grid}.feature-card{border-radius:var(--radius-md);box-shadow:var(--shadow-card);background:#fff;padding:20px}.feature-card h3{color:var(--green-600);margin-bottom:8px;font-size:1rem}.feature-card p{color:var(--gray-600);font-size:.9rem}.subjects-section{margin-bottom:40px}.subjects-section h2{text-align:center;color:var(--gray-900);margin-bottom:10px;font-size:1.4rem}.subjects-section>p{text-align:center;color:var(--gray-500);margin-bottom:20px;font-size:.9rem}.subjects-grid{grid-template-columns:1fr;gap:10px;display:grid}.subject-card{border-radius:var(--radius-md);box-shadow:var(--shadow-card);color:inherit;background:#fff;padding:18px;text-decoration:none;transition:box-shadow .15s;display:block}.subject-card:hover{box-shadow:var(--shadow-lg)}.subject-card h3{color:var(--green-600);margin-bottom:6px;font-size:1rem}.subject-card p{color:var(--gray-500);font-size:.85rem}.alert-box{border-radius:var(--radius-md);text-align:left;background:#fef2f2;border:2px solid #f87171;margin-bottom:40px;padding:24px}.alert-box h3{color:#b91c1c;margin-bottom:8px;font-size:1.15rem}.alert-box p{color:var(--gray-700);font-size:.9rem}.alert-box a{color:#b91c1c;font-weight:700}.faq-section{margin-bottom:40px}.faq-section h2{text-align:center;color:var(--gray-900);margin-bottom:20px;font-size:1.4rem}.faq-item{border-radius:var(--radius-sm);box-shadow:var(--shadow-card);background:#fff;margin-bottom:10px;padding:18px}.faq-item h3{color:var(--gray-800);margin-bottom:6px;font-size:1rem}.faq-item p{color:var(--gray-600);font-size:.88rem}.content-body{max-width:700px;margin:0 auto 50px}.content-body h2{color:var(--gray-900);margin:32px 0 12px;font-size:1.5rem}.content-body h3{color:var(--gray-700);margin:24px 0 10px;font-size:1.15rem}.content-body p{color:var(--gray-600);margin-bottom:14px;font-size:.95rem}.content-body ul,.content-body ol{color:var(--gray-600);margin:0 0 14px 20px;font-size:.95rem}.content-body li{margin-bottom:6px}.related-pages{background:var(--green-50);border-radius:var(--radius-md);margin:32px 0;padding:24px}.related-pages h3{color:var(--green-700);margin-bottom:12px}.related-pages ul{margin:0;padding:0;list-style:none}.related-pages li{margin-bottom:6px}.related-pages a{color:var(--green-600);font-weight:500;text-decoration:none}.related-pages a:hover{text-decoration:underline}.site-footer{border-top:1px solid var(--gray-200);text-align:center;margin-top:40px;padding:24px 0}.footer-links{flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:12px;display:flex}.footer-links a{color:var(--gray-400);font-size:.8rem;text-decoration:none}.footer-links a:hover{color:var(--green-600)}.site-footer p{color:var(--gray-400);font-size:.75rem}.site-nav{border-bottom:1px solid var(--gray-200);background:var(--gray-50);z-index:100;justify-content:space-between;align-items:center;margin-bottom:20px;padding:14px 0;display:flex;position:sticky;top:0}.nav-logo{color:var(--green-600);font-size:1.1rem;font-weight:700;text-decoration:none}.nav-links{gap:14px;display:flex}.nav-links a{color:var(--gray-500);font-size:.85rem;font-weight:500;text-decoration:none}.nav-links a:hover{color:var(--green-600)}@media (width<=600px){.site-nav{flex-direction:column;gap:8px}.nav-links{flex-wrap:wrap;justify-content:center;gap:10px}}@media (width>=700px){.features-grid{grid-template-columns:repeat(3,1fr)}.subjects-grid{grid-template-columns:repeat(2,1fr)}}.hero{text-align:center;margin-bottom:32px}.hero h1{color:var(--gray-900);margin-bottom:14px;font-size:1.8rem;line-height:1.2}.hero p{color:var(--gray-500);max-width:600px;margin-bottom:24px;margin-left:auto;margin-right:auto;font-size:1rem}.phone-mockup{box-shadow:var(--shadow-lg);background:#fff;border-radius:30px;max-width:360px;min-height:420px;margin:0 auto 40px;padding:16px;position:relative;overflow:hidden}.camera-view{border-radius:var(--radius-md);color:#fff;background:#0a0a0a;justify-content:center;align-items:center;height:300px;margin-bottom:16px;display:flex;position:relative}.btn-scan{background:var(--green-500);color:#fff;border-radius:var(--radius-full);cursor:pointer;border:none;margin:0 auto;padding:14px 36px;font-size:1.1rem;font-weight:600;display:block}.lang-switcher{background:var(--gray-100);border-bottom:1px solid var(--gray-200);flex-wrap:wrap;justify-content:center;gap:4px;padding:8px 16px;display:flex}.lang-switcher a{color:var(--gray-600);border-radius:var(--radius-full);padding:2px 8px;font-size:.75rem;text-decoration:none;transition:background .15s,color .15s}.lang-switcher a:hover{background:var(--gray-200);color:var(--gray-900)}.lang-switcher a.active{background:var(--green-500);color:#fff;font-weight:600}