/* LAYOUT STABILITY */
        .solver-page {
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            overflow-x: hidden;
        }
        
        /* ACCESSIBILITY */
        button:focus-visible {
            outline: 3px solid var(--text-info);
            outline-offset: 2px;
        }
        
        /* SEO CONTENT SECTION BASE */
        .seo-content-section {
            max-width: 1000px;
            margin: 40px auto;
            padding: 0 20px;
            width: 100%;
            box-sizing: border-box;
            overflow-x: hidden;
        }
        
        .seo-content-section h1 {
            font-size: clamp(1.5rem, 5vw, 2.2rem);
            margin-bottom: 1rem;
            color: var(--text-primary);
            text-align: center;
            word-wrap: break-word;
            overflow-wrap: break-word;
        }
        
        .seo-content-section .lead-text {
            font-size: clamp(1rem, 3vw, 1.15rem);
            line-height: 1.7;
            color: var(--text-secondary);
            margin-bottom: 2rem;
            text-align: center;
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
            word-wrap: break-word;
            overflow-wrap: break-word;
        }
        
        /* AI SUMMARY BOX (AEO) */
        .ai-summary-box {
            background: linear-gradient(135deg, var(--text-info) 0%, var(--accent-primary) 100%);
            color: var(--txt-func);
            padding: 24px;
            border-radius: 16px;
            margin-bottom: 32px;
            box-shadow: 0 10px 40px rgba(var(--ui-highlight-rgb), 0.3);
            width: 100%;
            box-sizing: border-box;
        }
        .ai-summary-box h2 {
            color: var(--txt-func);
            margin-top: 0;
            margin-bottom: 16px;
            font-size: clamp(1.2rem, 4vw, 1.5rem);
            word-wrap: break-word;
            text-shadow: 0 1px 2px var(--shadow-color);
        }
        .ai-summary-box ul {
            margin: 0;
            padding-left: 20px;
        }
        .ai-summary-box li {
            margin-bottom: 8px;
            line-height: 1.5;
            word-wrap: break-word;
            overflow-wrap: break-word;
            color: var(--txt-func);
            text-shadow: 0 1px 2px var(--shadow-color);
        }
        .ai-summary-box strong {
            color: var(--text-warning);
        }
        .ai-summary-title {
            color: var(--txt-func);
            margin-top: 0;
            margin-bottom: 16px;
            font-size: clamp(1.2rem, 4vw, 1.5rem);
            word-wrap: break-word;
            text-shadow: 0 1px 2px var(--shadow-color);
            font-weight: bold;
        }
        
        /* BREADCRUMB NAVIGATION */
        .breadcrumb-nav {
            background: var(--bg-secondary);
            border-bottom: 1px solid var(--border-color);
            padding: 12px 20px;
            font-size: 0.875rem;
            flex-shrink: 0;
        }
        .breadcrumb-list {
            list-style: none;
            padding: 0;
            margin: 0;
            display: flex;
            align-items: center;
            gap: 8px;
            max-width: 1400px;
            margin: 0 auto;
        }
        .breadcrumb-item {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .breadcrumb-item a {
            color: var(--text-secondary);
            text-decoration: none;
            transition: color 0.2s;
        }
        .breadcrumb-item a:hover {
            color: var(--ui-highlight);
        }
        .breadcrumb-item.active {
            color: var(--text-primary);
            font-weight: 600;
        }
        .breadcrumb-separator {
            color: var(--text-secondary);
            opacity: 0.5;
        }
        
        /* AUTHOR CARD (EEAT) */
        .author-card {
            display: flex;
            align-items: center;
            gap: 20px;
            background: var(--bg-secondary);
            padding: 24px;
            border-radius: 12px;
            border-left: 4px solid var(--text-info);
            margin: 32px 0;
        }
        .author-card img {
            width: 80px;
            height: 80px;
            border-radius: 50%;
            object-fit: cover;
        }
        .author-card h3 {
            margin: 0 0 4px 0;
            color: var(--text-primary);
            font-size: 1.2rem;
        }
        .author-title {
            color: var(--text-secondary);
            font-size: 0.9rem;
            margin-bottom: 8px;
        }
        .author-bio {
            color: var(--text-secondary);
            font-size: 0.9rem;
            line-height: 1.5;
            margin: 0;
        }
        .author-links {
            margin-top: 12px;
        }
        .author-links a {
            color: var(--ui-highlight);
            text-decoration: none;
            margin-right: 16px;
            font-size: 0.9rem;
        }
        .author-links a:hover {
            text-decoration: underline;
        }
        
        /* TRUST BADGES */
        .trust-badges {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            justify-content: center;
            margin: 24px 0;
            width: 100%;
        }
        .trust-badge-item {
            display: flex;
            align-items: center;
            gap: 6px;
            padding: 8px 14px;
            background: var(--bg-secondary);
            border-radius: 20px;
            font-size: 0.8rem;
            color: var(--text-secondary);
            white-space: nowrap;
        }
        
        /* FEATURE GRID */
        .feature-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 24px;
            margin: 32px 0;
            width: 100%;
        }
        .feature-card {
            background: var(--bg-secondary);
            padding: 25px;
            border-radius: 16px;
            border: 1px solid var(--border-color);
            transition: transform 0.2s ease, border-color 0.2s;
            word-wrap: break-word;
            overflow-wrap: break-word;
        }
        .feature-card:hover {
            transform: translateY(-5px);
            border-color: var(--ui-highlight);
        }
        .feature-card h3 {
            color: var(--text-primary);
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.2rem;
        }
        .feature-card p {
            color: var(--text-secondary);
            line-height: 1.6;
            margin-bottom: 0;
        }
        
        /* COMPARISON TABLE */
                /* Table Responsiveness */
        .table-wrapper {
            width: 100%;
            overflow-x: auto;
            -webkit-overflow-scrolling: touch;
            margin: 24px 0;
            border-radius: 12px;
            border: 1px solid var(--border-color);
            background: var(--bg-primary);
        }

.comparison-table {
            width: 100%;
            border-collapse: collapse;
            margin: 24px 0;
            background: var(--bg-primary);
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 4px 12px var(--shadow-color);
        }
        .comparison-table th {
            background: linear-gradient(135deg, var(--text-info) 0%, var(--accent-primary) 100%);
            color: var(--txt-func);
            padding: 16px;
            text-align: left;
        }
        .comparison-table td {
            padding: 16px;
            border-bottom: 1px solid var(--border-color);
            color: var(--text-secondary);
        }
        .comparison-table tr:last-child td {
            border-bottom: none;
        }
        .comparison-table .check::before {
            content: '✅';
            color: var(--text-success);
            font-weight: bold;
        }

        /* FAQ ACCORDION */
        .faq-section {
            margin-top: 40px;
            border-top: 1px solid var(--border-color);
            padding-top: 30px;
        }
        .faq-header {
            color: var(--text-primary);
            margin-bottom: 24px;
            font-size: 1.75rem;
            text-align: center;
        }
        .faq-item {
            border-bottom: 1px solid var(--border-color);
            margin-bottom: 10px;
        }
        .faq-question {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 20px 0;
            cursor: pointer;
            font-weight: 600;
            color: var(--text-primary);
            list-style: none;
            font-size: 1.1rem;
        }
        .faq-question::-webkit-details-marker {
            display: none;
        }
        .faq-icon {
            width: 10px;
            height: 10px;
            border-right: 2px solid var(--text-secondary);
            border-bottom: 2px solid var(--text-secondary);
            transform: rotate(45deg);
            transition: transform 0.2s;
        }
        details[open] .faq-icon {
            transform: rotate(225deg);
            border-color: var(--ui-highlight);
        }
        .faq-answer {
            color: var(--text-secondary);
            line-height: 1.7;
            padding-bottom: 20px;
        }
        .faq-answer p {
            margin: 0;
        }
        
        /* RELATED TOOLS */
        .related-tools {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 16px;
            margin: 24px 0;
        }
        .tool-card {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 16px;
            background: var(--bg-secondary);
            border-radius: 10px;
            text-decoration: none;
            border: 1px solid var(--border-color);
            transition: transform 0.2s, border-color 0.2s;
            color: var(--text-primary);
        }
        .tool-card:hover {
            transform: translateY(-3px);
            border-color: var(--ui-highlight);
        }
        .tool-card .icon {
            font-size: 1.5rem;
        }
        .tool-card h4 {
            margin: 0 0 4px 0;
            font-size: 1rem;
        }
        .tool-card span {
            font-size: 0.85rem;
            color: var(--text-secondary);
        }
        
        /* VERIFICATION METHODOLOGY */
        .verification-methodology {
            background: var(--bg-secondary);
            padding: 2rem;
            border-radius: 12px;
            border: 1px solid var(--border-color);
            margin: 32px 0;
            border-left: 4px solid var(--text-success);
        }
        .verification-methodology h2 {
            color: var(--text-primary);
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .verification-methodology ul {
            padding-left: 1.5rem;
            line-height: 1.8;
            color: var(--text-secondary);
            margin-bottom: 1rem;
        }
        .verification-methodology li {
            margin-bottom: 8px;
        }
        
        /* LEGAL DISCLAIMER */
        .legal-disclaimer-box {
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 20px;
            margin: 40px auto;
            max-width: 900px;
            text-align: center;
            font-size: 0.9rem;
            color: var(--text-secondary);
            border-left: 4px solid var(--ui-highlight);
        }
        .legal-disclaimer-box strong {
            color: var(--text-primary);
            display: block;
            margin-bottom: 8px;
        }
        .legal-disclaimer-box p {
            margin: 0;
            font-size: 0.85rem;
            text-align: center;
        }
        .legal-links {
            margin-top: 12px;
        }
        .legal-links a {
            color: var(--ui-highlight);
            text-decoration: none;
            margin: 0 8px;
        }
        
        /* USE CASE SECTIONS */
        .use-case-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 20px;
            margin: 24px 0;
        }
        .use-case-card {
            background: var(--bg-secondary);
            padding: 20px;
            border-radius: 12px;
            border: 1px solid var(--border-color);
        }
        .use-case-card h4 {
            margin-top: 0;
            color: var(--text-primary);
        }
        .use-case-card p {
            color: var(--text-secondary);
            font-size: 0.95rem;
            margin-bottom: 0;
        }
        
        /* FOOTER */
        .footer {
            background: var(--bg-secondary);
            padding: 40px 20px;
            margin-top: 40px;
            border-top: 1px solid var(--border-color);
        }
        .footer-content {
            max-width: 1200px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 30px;
        }
        .footer-col h4 {
            color: var(--text-primary);
            margin-bottom: 16px;
            font-size: 1rem;
        }
        .footer-col ul {
            list-style: none;
            padding: 0;
            margin: 0;
        }
        .footer-col li {
            margin-bottom: 8px;
        }
        .footer-col a {
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 0.9rem;
        }
        .footer-col a:hover {
            color: var(--ui-highlight);
        }
        .footer-bottom {
            text-align: center;
            margin-top: 30px;
            padding-top: 20px;
            border-top: 1px solid var(--border-color);
            
            color: var(--text-secondary);
            font-size: 0.85rem;
        }
        
        /* ========== SOLVER PAGE SPECIFIC FIXES ========== */
        .top-bar {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 12px 20px;
            background: var(--bg-secondary);
            border-bottom: 1px solid var(--border-color);
            gap: 12px;
            flex-wrap: wrap;
        }
        .top-bar-left {
            display: flex;
            align-items: center;
            gap: 8px;
            flex: 1;
        }
        .top-bar-center {
            flex: 1;
            text-align: center;
        }
        .top-bar-right {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        /* Sidebar Toggle Button */
        .sidebar-toggle-btn {
            display: none;
            background: var(--bg-tertiary);
            border: 1px solid var(--border-color);
            color: var(--text-primary);
            padding: 8px;
            border-radius: 8px;
            cursor: pointer;
            font-size: 1.125rem;
            margin-right: 8px;
        }
        
        /* Theme & Icon Buttons */
        .theme-toggle, .icon-btn {
            width: 40px;
            height: 40px;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--bg-tertiary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            cursor: pointer;
            font-size: 1.125rem;
            transition: all 0.2s;
            color: var(--text-primary);
        }
        .theme-toggle:hover, .icon-btn:hover {
            background: var(--ui-highlight);
            color: var(--txt-func);
            border-color: var(--ui-highlight);
        }
        
        /* AI Tutor Label */
        .ai-tutor-label {
            font-weight: 600;
            color: var(--text-info);
            font-size: 0.9rem;
            padding: 4px 12px;
            background: rgba(30, 144, 255, 0.1);
            border-radius: 20px;
            border: 1px solid var(--text-info);
        }
        
        /* Solver Layout */
        .solver-layout {
            display: flex;
            flex: 1;
            min-height: calc(100vh - 200px);
        }
        
        .solver-sidebar {
            width: 280px;
            background: var(--bg-secondary);
            border-right: 1px solid var(--border-color);
            overflow-y: auto;
            transition: transform 0.3s ease;
        }
        
        .solver-sidebar-overlay {
            display: none;
            position: fixed;
            inset: 0;
            background: rgba(0,0,0,0.5);
            z-index: 1999;
        }
        
        .chat-container {
            flex: 1;
            display: flex;
            flex-direction: column;
            max-width: none;
        }
        
        .solution-area {
            flex: 1;
            overflow-y: auto;
            padding: 20px;
        }
        
        .input-wrapper {
            padding: 0 20px 20px;
            width: 100%;
            box-sizing: border-box;
            display: flex;
            justify-content: center;
        }
        
        .input-box {
            display: flex;
            gap: 12px;
            background: var(--bg-primary);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 8px;
            max-width: 800px;
            width: 100%;
            margin: 0 auto;
            box-sizing: border-box;
        }
        
        .problem-input {
            flex: 1;
            border: none;
            background: transparent;
            color: var(--text-primary);
            font-size: 1rem;
            padding: 12px;
            outline: none;
            min-width: 0; /* Allow input to shrink */
            width: 100%;
            box-sizing: border-box;
        }
        
        .solve-btn {
            background: var(--ui-highlight);
            color: var(--txt-func);
            border: none;
            padding: 12px 24px;
            border-radius: 8px;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 8px;
            white-space: nowrap;
        }
        
        .solve-btn:hover {
            opacity: 0.9;
        }
        
        .solve-btn:disabled {
            opacity: 0.6;
            cursor: not-allowed;
        }
        
        .loader {
            width: 16px;
            height: 16px;
            border: 2px solid rgba(var(--text-primary-rgb), 0.15);
            border-top-color: var(--text-primary);
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }
        
        @keyframes spin {
            to { transform: rotate(360deg); }
        }
        
        @keyframes slideInRight {
            from { transform: translateX(100%); opacity: 0; }
            to { transform: translateX(0); opacity: 1; }
        }
        
        .metrics-bar {
            display: flex;
            gap: 16px;
            padding: 8px 20px;
            background: var(--bg-secondary);
            font-size: 0.75rem;
            justify-content: center;
            border-top: 1px solid var(--border-color);
            position: relative;
            z-index: 10;
        }
        
        .metric {
            display: flex;
            flex-direction: column;
            align-items: center;
        }
        
        .metric-label {
            color: var(--text-secondary);
            font-size: 0.625rem;
        }
        
        .metric-value {
            color: var(--text-primary);
            font-weight: 600;
        }
        
        /* Placeholder Content */
        .placeholder-content {
            text-align: center;
            padding: 40px 20px;
        }
        
        .ai-icon {
            font-size: 4rem;
            margin-bottom: 20px;
        }
        
        .placeholder-content h2 {
            color: var(--text-primary);
            margin-bottom: 16px;
        }
        
        .placeholder-content p {
            color: var(--text-secondary);
            max-width: 500px;
            margin: 0 auto 24px;
        }
        
        .example-buttons {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            justify-content: center;
            margin-bottom: 32px;
        }
        
        .example-btn {
            padding: 10px 16px;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 20px;
            cursor: pointer;
            font-size: 0.8125rem;
            color: var(--text-primary);
            transition: all 0.2s;
        }
        
        .example-btn:hover {
            border-color: var(--ui-highlight);
            color: var(--ui-highlight);
        }
        
        .feature-highlights {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            justify-content: center;
        }
        
        .feature-item {
            padding: 8px 16px;
            background: var(--bg-secondary);
            border-radius: 20px;
            font-size: 0.8125rem;
            color: var(--text-secondary);
        }
        
        /* History Sidebar */
        .sidebar-header {
            padding: 16px;
            border-bottom: 1px solid var(--border-color);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 600;
            color: var(--text-primary);
        }
        
        .history-list {
            padding: 10px;
        }
        
        .history-item {
            padding: 12px;
            border-bottom: 1px solid var(--border-color);
            cursor: pointer;
            transition: background 0.2s;
        }
        
        .history-item:hover {
            background: var(--bg-tertiary);
        }
        
        .history-problem {
            font-size: 0.875rem;
            color: var(--text-primary);
            margin-bottom: 4px;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }
        
        .history-time {
            font-size: 0.75rem;
            color: var(--text-secondary);
        }
        
        /* Heavy Calculation Loading Indicator */
        .calculation-loading {
            position: fixed;
            top: 20px;
            right: 20px;
            background: var(--ui-highlight);
            color: var(--txt-func);
            padding: 10px 16px;
            border-radius: 8px;
            font-weight: 600;
            font-size: 0.8125rem;
            z-index: 4000;
            display: flex;
            align-items: center;
            gap: 8px;
            box-shadow: 0 4px 12px var(--shadow-color);
            opacity: 0;
            transform: translateY(-20px);
            transition: opacity 0.2s, transform 0.2s;
            pointer-events: none;
        }
        .calculation-loading.active { opacity: 1; transform: translateY(0); }
        .calculation-loading::before {
            content: '';
            width: 16px;
            height: 16px;
            border: 2px solid rgba(var(--text-primary-rgb), 0.15);
            border-top-color: var(--text-primary);
            border-radius: 50%;
            animation: spin 0.8s linear infinite;
        }
        @keyframes spin { to { transform: rotate(360deg); } }
        
        /* Touch action for buttons */
        .solve-btn, .example-btn, .icon-btn, .theme-toggle {
            touch-action: manipulation;
            -webkit-tap-highlight-color: transparent;
        }
        
        /* Mobile input font size to prevent zoom */
        .chat-input, .text-input {
            font-size: 1rem;
        }
        
        @media (min-width: 769px) {
            .chat-input, .text-input {
                font-size: 1rem;
            }
        }
        
        /* Mobile Responsive */
        @media (max-width: 768px) {
            .solver-page {
                width: 100vw;
                max-width: 100vw;
                overflow-x: hidden;
            }
            
            .breadcrumb-list {
                overflow-x: auto;
                white-space: nowrap;
            }
            
            .sidebar-toggle-btn {
                display: flex;
            }
            
            .top-bar {
                padding: 10px 15px;
                flex-wrap: nowrap;
                width: 100%;
                box-sizing: border-box;
                gap: 8px;
            }
            
            .top-bar-left {
                flex: 0 0 auto;
                display: flex;
                align-items: center;
            }
            
            .top-bar-center {
                flex: 1;
                text-align: center;
                min-width: 0;
            }
            
            .top-bar-right {
                flex: 0 0 auto;
                display: flex;
                align-items: center;
                gap: 6px;
            }
            
            .ai-tutor-label {
                font-size: 0.7rem;
                padding: 2px 6px;
                white-space: nowrap;
                max-width: 100%;
                overflow: hidden;
                text-overflow: ellipsis;
                display: inline-block;
            }
            
            /* Fix header to full width */
            .header {
                width: 100%;
                box-sizing: border-box;
            }
            
            .header-content {
                width: 100%;
                box-sizing: border-box;
            }
            
            /* Better solution scrolling */
            .solution-area {
                scroll-behavior: smooth;
                -webkit-overflow-scrolling: touch;
            }
            
            /* Improved solution content styling */
            .step-content {
                padding: 16px;
                font-size: 0.9375rem;
                line-height: 1.7;
            }
            
            .step-content h1,
            .step-content h2,
            .step-content h3 {
                font-size: 1.2rem;
                margin-top: 16px;
                margin-bottom: 12px;
                color: var(--ui-highlight);
            }
            
            .step-content h2 {
                font-size: 1.1rem;
            }
            
            .step-content h3 {
                font-size: 1rem;
            }
            
            .step-content p {
                margin-bottom: 12px;
            }
            
            .step-content ul,
            .step-content ol {
                padding-left: 20px;
                margin-bottom: 12px;
            }
            
            .step-content li {
                margin-bottom: 8px;
            }
            
            /* Highlight important parts */
            .step-content strong {
                color: var(--text-info);
                font-weight: 600;
            }
            
            .step-content code {
                background: var(--bg-tertiary);
                padding: 2px 6px;
                border-radius: 4px;
                font-family: 'Courier New', monospace;
                font-size: 0.9em;
                color: var(--text-warning);
            }
            
            /* Better blockquote styling */
            .step-content blockquote {
                border-left: 3px solid var(--ui-highlight);
                margin: 12px 0;
                padding: 12px 16px;
                background: var(--bg-tertiary);
                border-radius: 0 8px 8px 0;
                font-style: italic;
            }
            
            .solver-layout {
                position: relative;
                width: 100%;
                display: flex;
                flex-direction: column;
                align-items: center;
            }
            
            .solver-sidebar {
                position: fixed;
                left: 0;
                top: 0;
                bottom: 0;
                width: 280px;
                max-width: 80vw;
                z-index: 2000;
                transform: translateX(-100%);
                box-shadow: 2px 0 10px var(--shadow-color);
            }
            
            .solver-sidebar.active {
                transform: translateX(0);
            }
            
            .solver-sidebar-overlay.active {
                display: block;
            }
            
            .chat-container {
                width: 100%;
                display: flex;
                flex-direction: column;
                align-items: center;
            }
            
            .example-buttons {
                flex-direction: column;
                padding: 0 20px;
                width: 100%;
                max-width: 600px;
                margin: 0 auto;
            }
            
            .example-btn {
                width: 100%;
                text-align: center;
            }
            
            .input-box {
                margin: 0 auto;
                width: calc(100% - 30px);
                max-width: 600px;
            }
            
            .author-card {
                flex-direction: column;
                text-align: center;
                padding: 20px;
            }
            
            /* SEO Content mobile fixes */
            .seo-content-section {
                padding: 30px 15px;
                width: 100%;
            }
            
            .seo-content-section h1 {
                font-size: 1.5rem;
                margin-bottom: 0.75rem;
            }
            
            .seo-content-section .lead-text {
                font-size: 1rem;
                margin-bottom: 1.5rem;
                padding: 0 8px;
            }
            
            .ai-summary-box {
                padding: 20px;
                margin-bottom: 24px;
            }
            
            .ai-summary-box h2 {
                font-size: 1.2rem;
            }
            
            .ai-summary-box ul {
                padding-left: 18px;
            }
            
            .ai-summary-box li {
                font-size: 0.9rem;
                margin-bottom: 6px;
            }
            
            .trust-badges {
                gap: 8px;
                margin: 20px 0;
            }
            
            .trust-badge-item {
                padding: 6px 12px;
                font-size: 0.75rem;
            }
            
            .feature-grid {
                grid-template-columns: 1fr;
                gap: 16px;
                margin: 24px 0;
            }
            
            .feature-card {
                padding: 20px;
            }
            
            .feature-card h3 {
                font-size: 1.1rem;
            }
        }
        
        @media (max-width: 480px) {
            /* Main Header Fix - Full width and proper layout */
            html, body {
                width: 100vw;
                max-width: 100vw;
                overflow-x: hidden;
            }
            
            .header {
                padding: 10px 15px;
                width: 100%;
                box-sizing: border-box;
            }
            
            .header-content {
                width: 100%;
                box-sizing: border-box;
                display: flex;
                align-items: center;
                justify-content: space-between;
            }
            
            .header-content {
                display: flex;
                align-items: center;
                justify-content: space-between;
                width: 100%;
            }
            
            .logo-area {
                flex: 1;
                text-align: left;
            }
            
            .logo-text h1 {
                font-size: 1.25rem !important;
            }
            
            .tagline {
                font-size: 0.7rem !important;
            }
            
            .mobile-menu-btn {
                order: 2;
                margin-left: 10px;
                flex-shrink: 0;
            }
            
            .top-bar {
                padding: 10px 12px;
                flex-wrap: nowrap; /* Prevent wrapping */
                gap: 8px;
            }
            
            .top-bar-left {
                flex: 0 0 auto; /* Don't grow/shrink */
                order: 1;
            }
            
            .top-bar-center {
                order: 2;
                flex: 1; /* Take remaining space */
                text-align: center;
                margin-top: 0;
                width: auto;
            }
            
            .top-bar-right {
                order: 3;
                flex: 0 0 auto; /* Don't grow/shrink */
                gap: 6px;
            }
            
            .ai-tutor-label {
                display: inline-block;
                font-size: 0.65rem;
                padding: 2px 6px;
                white-space: nowrap;
                max-width: 100%;
                overflow: hidden;
                text-overflow: ellipsis;
            }
            
            .theme-toggle, .icon-btn {
                width: 36px;
                height: 36px;
                font-size: 1rem;
            }
            
            .solve-btn {
                padding: 10px 16px;
                font-size: 0.875rem;
                min-width: 70px;
            }
            
            .solve-btn span {
                display: inline;
                font-size: 0.875rem;
            }
            
            .feature-highlights {
                flex-direction: column;
                align-items: center;
            }
            
            /* Center main content properly */
            .chat-container {
                width: 100%;
                max-width: 100%;
                display: flex;
                flex-direction: column;
                align-items: center;
            }
            
            .solution-area {
                padding: 15px;
                width: 100%;
                max-width: 800px;
                box-sizing: border-box;
            }
            
            .placeholder-content {
                padding: 20px 15px;
                text-align: center;
                width: 100%;
                box-sizing: border-box;
            }
            
            .placeholder-content h2 {
                font-size: 1.375rem;
            }
            
            .placeholder-content p {
                max-width: 100%;
                padding: 0 15px;
            }
            
            /* Ensure input box is centered */
            .input-wrapper {
                left: 0;
                right: 0;
                width: 100%;
            }
            
            .input-box {
                margin: 0 auto;
                width: calc(100% - 30px);
                max-width: 600px;
                box-sizing: border-box;
            }
            
            /* Solution area mobile improvements */
            .solution-area {
                padding: 15px;
            }
            
            .solution-content {
                padding: 16px;
                margin-bottom: 16px;
                border-radius: 12px;
            }
            
            .solution-header {
                flex-wrap: wrap;
                gap: 8px;
                margin-bottom: 12px;
                padding-bottom: 10px;
            }
            
            .solution-metadata {
                width: 100%;
                justify-content: flex-start;
            }
            
            .solution-body {
                font-size: 0.9375rem;
                line-height: 1.7;
            }
            
            .solution-body h1 {
                font-size: 1.25rem;
                margin: 20px 0 12px;
            }
            
            .solution-body h2 {
                font-size: 1.125rem;
                margin: 18px 0 10px;
            }
            
            .solution-body h3 {
                font-size: 1rem;
                margin: 16px 0 8px;
            }
            
            .solution-body ul, .solution-body ol {
                padding-left: 20px;
            }
            
            .solution-body pre {
                padding: 12px;
                font-size: 0.8125rem;
            }
            
            .solution-actions {
                flex-direction: column !important;
                width: 100%;
            }
            
            .solution-actions button {
                width: 100%;
                justify-content: center;
            }
            
            /* Fixed input bar on mobile - clean layout */
            .input-wrapper {
                position: sticky;
                bottom: 0;
                padding: 12px 15px;
                background: var(--bg-primary);
                border-top: 1px solid var(--border-color);
                z-index: 100;
                margin-top: auto;
                width: 100%;
                box-sizing: border-box;
                display: flex;
                justify-content: center;
            }
            
            .input-box {
                margin: 0 auto;
                width: 100%;
                max-width: 600px;
                display: flex;
                gap: 8px;
                box-sizing: border-box;
            }
            
            .problem-input {
                font-size: 1rem; /* Prevent zoom on iOS */
                min-height: 44px;
            }
            
            .solve-btn {
                padding: 10px 18px;
                min-height: 44px;
                display: flex;
                align-items: center;
                justify-content: center;
            }
            
            .solve-btn span {
                display: inline !important;
                font-size: 0.875rem;
                font-weight: 600;
            }
            
            /* Metrics bar - static position, no floating */
            .metrics-bar {
                position: static;
                background: var(--bg-secondary);
                padding: 8px 15px;
                border-top: 1px solid var(--border-color);
                border-bottom: 1px solid var(--border-color);
                margin: 0;
                width: 100%;
                box-sizing: border-box;
            }
            
            .metric {
                display: flex;
                flex-direction: column;
                align-items: center;
                gap: 2px;
            }
            
            .metric-label {
                font-size: 0.625rem;
                color: var(--text-secondary);
                text-transform: uppercase;
            }
            
            .metric-value {
                font-size: 0.75rem;
                font-weight: 600;
                color: var(--text-primary);
            }
            
            .solution-area {
                padding: 15px;
                padding-bottom: 20px;
                min-height: auto;
            }
            
            .solver-layout {
                min-height: calc(100vh - 120px);
                display: flex;
                flex-direction: column;
            }
            
            .chat-container {
                display: flex;
                flex-direction: column;
                min-height: 100%;
            }
        }
        
        /* TOUCH-FRIENDLY IMPROVEMENTS */
        @media (hover: none) and (pointer: coarse) {
            .solve-btn, .action-btn, .example-btn, .icon-btn {
                min-height: 44px; /* iOS recommended touch target */
                min-width: 44px;
            }
            
            .history-item {
                padding: 16px;
            }
        }
        
        /* SOLUTION DISPLAY - MAIN UI */
        .solution-content {
            animation: fadeInUp 0.4s ease-out;
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border: 1px solid var(--border-color);
            border-radius: 16px;
            padding: 24px;
            margin-bottom: 20px;
            box-shadow: 0 4px 20px var(--shadow-color);
            scroll-margin-top: 20px;
        }
        
        /* Enhanced Solution Body Styling */
        .solution-body {
            color: var(--text-primary);
            line-height: 1.9;
            font-size: 1rem;
        }
        
        .solution-body h1 {
            color: var(--ui-highlight);
            font-size: 1.5rem;
            margin: 24px 0 16px;
            padding-bottom: 12px;
            border-bottom: 3px solid var(--border-color);
            font-weight: 700;
        }
        
        .solution-body h2 {
            color: var(--ui-highlight);
            font-size: 1.25rem;
            margin: 24px 0 12px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--border-color);
            font-weight: 600;
        }
        
        .solution-body h3 {
            color: var(--text-primary);
            font-size: 1.125rem;
            margin: 20px 0 10px;
            font-weight: 600;
        }
        
        .solution-body h4 {
            color: var(--text-secondary);
            font-size: 1rem;
            margin: 16px 0 8px;
            font-weight: 600;
        }
        
        .solution-body p {
            margin-bottom: 16px;
            text-align: left;
        }
        
        .solution-body strong {
            color: var(--ui-highlight);
            font-weight: 600;
        }
        
        .solution-body ul, .solution-body ol {
            margin: 16px 0;
            padding-left: 28px;
        }
        
        .solution-body li {
            margin-bottom: 10px;
            line-height: 1.7;
        }
        
        .solution-body code {
            background: var(--bg-tertiary);
            padding: 3px 8px;
            border-radius: 6px;
            font-family: 'Courier New', monospace;
            font-size: 0.875rem;
            color: var(--text-warning);
            border: 1px solid var(--border-color);
        }
        
        .solution-body pre {
            background: var(--bg-tertiary);
            padding: 20px;
            border-radius: 12px;
            overflow-x: auto;
            border: 1px solid var(--border-color);
            margin: 16px 0;
            font-family: 'Courier New', monospace;
            font-size: 0.875rem;
            line-height: 1.6;
        }
        
        .solution-body pre code {
            background: transparent;
            border: none;
            padding: 0;
            color: var(--text-primary);
        }
        
        .solution-body blockquote {
            border-left: 4px solid var(--ui-highlight);
            margin: 20px 0;
            padding: 16px 20px;
            background: var(--bg-tertiary);
            border-radius: 0 12px 12px 0;
            font-style: italic;
            color: var(--text-secondary);
        }
        
        .solution-body table {
            width: 100%;
            border-collapse: collapse;
            margin: 20px 0;
            background: var(--bg-primary);
            border-radius: 8px;
            overflow: hidden;
        }
        
        .solution-body th,
        .solution-body td {
            padding: 12px 16px;
            text-align: left;
            border-bottom: 1px solid var(--border-color);
        }
        
        .solution-body th {
            background: var(--bg-tertiary);
            font-weight: 600;
            color: var(--ui-highlight);
        }
        
        .solution-body tr:last-child td {
            border-bottom: none;
        }
        
        /* Smooth scrolling for solution area */
        .solution-area {
            scroll-behavior: smooth;
            -webkit-overflow-scrolling: touch;
        }
        
        /* Highlight animation for new solutions */
        @keyframes highlightSolution {
            0% { box-shadow: 0 0 0 0 rgba(var(--ui-highlight-rgb), 0.4); }
            50% { box-shadow: 0 0 0 10px rgba(var(--ui-highlight-rgb), 0); }
            100% { box-shadow: 0 0 0 0 rgba(var(--ui-highlight-rgb), 0); }
        }
        
        .solution-content.new-solution {
            animation: fadeInUp 0.4s ease-out, highlightSolution 1s ease-out;
        }
        
        .solution-header {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 16px;
            padding-bottom: 12px;
            border-bottom: 1px solid var(--border-color);
        }
        
        .ai-avatar {
            font-size: 1.5rem;
        }
        
        .ai-label {
            font-weight: 600;
            color: var(--text-primary);
            flex: 1;
        }
        
        .solution-metadata {
            display: flex;
            gap: 12px;
            font-size: 0.75rem;
            color: var(--text-secondary);
        }
        
        .solution-body {
            color: var(--text-primary);
            line-height: 1.8;
            font-size: 1rem;
        }
        
        .solution-body h2 {
            color: var(--ui-highlight);
            font-size: 1.25rem;
            margin: 20px 0 12px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--border-color);
        }
        
        .solution-body h3 {
            color: var(--text-primary);
            font-size: 1.125rem;
            margin: 16px 0 10px;
        }
        
        .solution-body h4 {
            color: var(--text-secondary);
            font-size: 1rem;
            margin: 14px 0 8px;
        }
        
        .solution-body strong {
            color: var(--ui-highlight);
            font-weight: 600;
        }
        
        .solution-body code {
            background: var(--bg-primary);
            padding: 2px 6px;
            border-radius: 4px;
            font-family: 'Courier New', monospace;
            font-size: 0.875rem;
        }
        
        .solution-body pre {
            background: var(--bg-primary);
            padding: 16px;
            border-radius: 8px;
            overflow-x: auto;
            border: 1px solid var(--border-color);
        }
        
        /* SMOOTH ANIMATIONS */
        .solution-content {
            animation: fadeInUp 0.4s ease-out;
        }
        
        @keyframes fadeInUp {
            from {
                opacity: 0;
                transform: translateY(20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }
        
        /* SOLUTION ACTIONS */
        .solution-actions button {
            padding: 8px 16px;
            border-radius: 6px;
            border: 1px solid var(--border-color);
            background: var(--bg-primary);
            color: var(--text-primary);
            cursor: pointer;
            transition: all 0.2s;
            font-size: 0.8125rem;
        }
        
        .solution-actions button:hover {
            background: var(--ui-highlight);
            color: var(--txt-func);
            border-color: var(--ui-highlight);
        }
        
        /* LOADING STATE */
        .solving-indicator {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 12px;
            padding: 40px;
            color: var(--text-secondary);
        }
        
        .solving-indicator .loader {
            width: 24px;
            height: 24px;
            border: 3px solid var(--border-color);
            border-top-color: var(--ui-highlight);
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }
        
        /* ==================== EXPLAIN MORE MODAL ==================== */
        .explain-more-modal {
            display: none;
            position: fixed;
            inset: 0;
            z-index: 9999;
            align-items: center;
            justify-content: center;
            padding: 20px;
        }
        
        .explain-more-modal.active {
            display: flex;
        }
        
        .explain-more-overlay {
            position: absolute;
            inset: 0;
            background: rgba(0, 0, 0, 0.85);
            backdrop-filter: blur(8px);
            -webkit-backdrop-filter: blur(8px);
            animation: fadeIn 0.3s ease;
        }
        
        .explain-more-container {
            position: relative;
            width: 90%;
            max-width: 900px;
            max-height: 85vh;
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
            border-radius: 16px;
            box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(0,0,0,0.1);
            display: flex;
            flex-direction: column;
            overflow: hidden;
            animation: slideUp 0.4s cubic-bezier(0.16, 1, 0.3, 1);
            border: 1px solid rgba(0,0,0,0.15);
        }
        
        /* Dark theme modal - uses dark backgrounds */
        [data-theme="dark"] .explain-more-container,
        [data-theme="solar"] .explain-more-container {
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
            border: 2px solid var(--border-color);
        }
        
        /* Force solid background for all modal contents - LIGHT THEME */
        .explain-more-header {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-bottom: 2px solid var(--border-color);
        }
        
        .explain-more-content {
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        .explain-more-footer {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-top: 2px solid var(--border-color);
        }
        
        /* Dark/Solar theme overrides */
        [data-theme="dark"] .explain-more-header,
        [data-theme="solar"] .explain-more-header {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-bottom: 2px solid var(--border-color);
        }
        
        [data-theme="dark"] .explain-more-content,
        [data-theme="solar"] .explain-more-content {
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        [data-theme="dark"] .explain-more-footer,
        [data-theme="solar"] .explain-more-footer {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-top: 2px solid var(--border-color);
        }
        
        @keyframes slideUp {
            from {
                opacity: 0;
                transform: translateY(30px) scale(0.95);
            }
            to {
                opacity: 1;
                transform: translateY(0) scale(1);
            }
        }
        
        .explain-more-header {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 20px 24px;
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-bottom: 2px solid var(--border-color);
        }
        
        .explain-title {
            display: flex;
            align-items: center;
            gap: 16px;
        }
        
        .explain-icon {
            font-size: 2rem;
            animation: pulse 2s infinite;
        }
        
        .explain-title h2 {
            margin: 0;
            font-size: 1.5rem;
            color: var(--text-primary) !important;
            font-weight: 700;
        }
        
        [data-theme="dark"] .explain-title h2,
        [data-theme="solar"] .explain-title h2 {
            color: var(--text-primary) !important;
        }
        
        .explain-subtitle {
            margin: 4px 0 0 0;
            font-size: 0.8125rem;
            color: var(--text-tertiary) !important;
        }
        
        [data-theme="dark"] .explain-subtitle,
        [data-theme="solar"] .explain-subtitle {
            color: var(--text-secondary) !important;
        }
        
        .close-explain-btn {
            background: none;
            border: none;
            font-size: 1.5rem;
            color: var(--text-tertiary) !important;
            cursor: pointer;
            padding: 8px;
            border-radius: 8px;
            transition: all 0.2s;
            width: 40px;
            height: 40px;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        
        .close-explain-btn:hover {
            background: var(--bg-tertiary) !important;
            color: var(--text-primary) !important;
        }
        
        [data-theme="dark"] .close-explain-btn,
        [data-theme="solar"] .close-explain-btn {
            color: var(--text-secondary) !important;
        }
        
        [data-theme="dark"] .close-explain-btn:hover,
        [data-theme="solar"] .close-explain-btn:hover {
            background: var(--bg-secondary) !important;
            color: var(--text-primary) !important;
        }
        
        .explain-more-content {
            flex: 1;
            overflow-y: auto;
            padding: 24px;
            scroll-behavior: smooth;
            background-color: var(--bg-primary) !important;
            background: var(--bg-primary) !important;
        }
        
        /* Custom scrollbar */
        .explain-more-content::-webkit-scrollbar {
            width: 8px;
        }
        
        .explain-more-content::-webkit-scrollbar-track {
            background: var(--bg-secondary);
            border-radius: 4px;
        }
        
        .explain-more-content::-webkit-scrollbar-thumb {
            background: var(--border-color);
            border-radius: 4px;
        }
        
        .explain-more-content::-webkit-scrollbar-thumb:hover {
            background: var(--text-secondary);
        }
        
        .explain-more-footer {
            padding: 16px 24px;
            border-top: 2px solid var(--border-color);
            background-color: var(--bg-secondary) !important;
            background: var(--bg-secondary) !important;
            display: flex;
            justify-content: flex-end;
        }
        
        .close-modal-btn {
            background: linear-gradient(135deg, var(--ui-highlight) 0%, var(--bg-tertiary) 100%);
            color: var(--txt-func);
            border: none;
            padding: 12px 32px;
            border-radius: 8px;
            font-size: 0.9375rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
        }
        
        .close-modal-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(var(--ui-highlight-rgb), 0.4);
        }
        
        /* Deep Explanation Content Styling - LIGHT THEME */
        .deep-explanation {
            color: var(--text-primary) !important;
            line-height: 1.9;
            font-size: 1rem;
        }
        
        [data-theme="dark"] .deep-explanation,
        [data-theme="solar"] .deep-explanation {
            color: var(--text-primary) !important;
        }
        
        /* Enhanced Deep Explanation Content Styling */
        .deep-explanation h1 {
            color: var(--ui-highlight) !important;
            font-size: 1.625rem;
            margin: 28px 0 18px;
            padding-bottom: 12px;
            border-bottom: 3px solid var(--border-color);
            font-weight: 700;
        }
        
        [data-theme="dark"] .deep-explanation h1,
        [data-theme="solar"] .deep-explanation h1 {
            color: var(--ui-highlight) !important;
            border-bottom-color: var(--border-color);
        }
        
        .deep-explanation h2 {
            color: var(--ui-highlight) !important;
            font-size: 1.375rem;
            margin: 24px 0 14px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--border-color);
            font-weight: 600;
        }
        
        [data-theme="dark"] .deep-explanation h2,
        [data-theme="solar"] .deep-explanation h2 {
            color: var(--ui-highlight) !important;
            border-bottom-color: var(--border-color);
        }
        
        .deep-explanation h3 {
            color: var(--text-secondary) !important;
            font-size: 1.1875rem;
            margin: 20px 0 12px;
            font-weight: 600;
        }
        
        [data-theme="dark"] .deep-explanation h3,
        [data-theme="solar"] .deep-explanation h3 {
            color: var(--text-primary) !important;
        }
        
        .deep-explanation p {
            margin-bottom: 16px;
        }
        
        .deep-explanation strong {
            color: var(--ui-highlight) !important;
            font-weight: 600;
        }
        
        [data-theme="dark"] .deep-explanation strong,
        [data-theme="solar"] .deep-explanation strong {
            color: var(--ui-highlight) !important;
        }
        
        .deep-explanation ul, .deep-explanation ol {
            margin: 16px 0;
            padding-left: 28px;
        }
        
        .deep-explanation li {
            margin-bottom: 10px;
            line-height: 1.7;
        }
        
        .deep-explanation code {
            background: var(--bg-secondary) !important;
            padding: 3px 8px;
            border-radius: 6px;
            font-family: 'Courier New', monospace;
            font-size: 0.875rem;
            color: var(--text-warning) !important;
            border: 1px solid var(--border-color);
        }
        
        [data-theme="dark"] .deep-explanation code,
        [data-theme="solar"] .deep-explanation code {
            background: var(--bg-tertiary) !important;
            color: var(--text-warning) !important;
            border-color: var(--border-color);
        }
        
        .deep-explanation pre {
            background: var(--bg-secondary) !important;
            padding: 20px;
            border-radius: 12px;
            overflow-x: auto;
            border: 1px solid var(--border-color);
            margin: 16px 0;
            font-family: 'Courier New', monospace;
            font-size: 0.875rem;
        }
        
        [data-theme="dark"] .deep-explanation pre,
        [data-theme="solar"] .deep-explanation pre {
            background: var(--bg-tertiary) !important;
            border-color: var(--border-color);
        }
        
        .deep-explanation blockquote {
            border-left: 4px solid var(--ui-highlight);
            margin: 20px 0;
            padding: 16px 20px;
            background: var(--bg-secondary) !important;
            border-radius: 0 12px 12px 0;
            font-style: italic;
            color: var(--text-secondary) !important;
        }
        
        [data-theme="dark"] .deep-explanation blockquote,
        [data-theme="solar"] .deep-explanation blockquote {
            border-left-color: var(--ui-highlight);
            background: var(--bg-secondary) !important;
            color: var(--text-secondary) !important;
        }
        
        .explain-intro {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 16px 20px;
            background: var(--bg-tertiary) !important;
            background-color: var(--bg-tertiary) !important;
            border-radius: 12px;
            margin-bottom: 24px;
            border-left: 4px solid var(--ui-highlight);
            border: 1px solid var(--border-color);
        }
        
        [data-theme="dark"] .explain-intro,
        [data-theme="solar"] .explain-intro {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-left: 4px solid var(--ui-highlight);
            border: 1px solid var(--border-color);
        }
        
        .intro-icon {
            font-size: 1.75rem;
        }
        
        .explain-intro p {
            margin: 0;
            font-size: 0.9375rem;
            color: var(--text-primary) !important;
        }
        
        [data-theme="dark"] .explain-intro p,
        [data-theme="solar"] .explain-intro p {
            color: var(--text-primary) !important;
        }
        
        .explain-section {
            margin-bottom: 24px;
            padding: 20px;
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border-radius: 12px;
            border: 1px solid var(--border-color);
        }
        
        [data-theme="dark"] .explain-section,
        [data-theme="solar"] .explain-section {
            background: var(--bg-secondary) !important;
            background-color: var(--bg-secondary) !important;
            border: 1px solid var(--border-color);
        }
        
        .explain-section-title {
            font-size: 1.125rem;
            font-weight: 700;
            color: var(--text-secondary) !important;
            margin: 0 0 16px 0;
            padding-bottom: 12px;
            border-bottom: 2px solid var(--border-color);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        [data-theme="dark"] .explain-section-title,
        [data-theme="solar"] .explain-section-title {
            color: var(--ui-highlight) !important;
            border-bottom: 2px solid var(--border-color);
        }
        
        .explain-subsection {
            font-size: 1rem;
            font-weight: 600;
            color: var(--text-secondary) !important;
            margin: 20px 0 12px 0;
        }
        
        [data-theme="dark"] .explain-subsection,
        [data-theme="solar"] .explain-subsection {
            color: var(--text-primary) !important;
        }
        
        .explain-main-title {
            font-size: 1.375rem;
            font-weight: 700;
            color: var(--text-primary) !important;
            margin: 0 0 20px 0;
        }
        
        [data-theme="dark"] .explain-main-title,
        [data-theme="solar"] .explain-main-title {
            color: var(--text-primary) !important;
        }
        
        .explain-highlight {
            background: rgba(var(--ui-highlight-rgb), 0.15) !important;
            padding: 2px 6px;
            border-radius: 4px;
            color: var(--text-secondary) !important;
            font-weight: 600;
        }
        
        [data-theme="dark"] .explain-highlight,
        [data-theme="solar"] .explain-highlight {
            background: linear-gradient(135deg, rgba(var(--ui-highlight-rgb), 0.15) 0%, rgba(118, 75, 162, 0.15) 100%) !important;
            color: var(--ui-highlight) !important;
        }
        
        .explain-list {
            margin: 12px 0;
            padding-left: 20px;
        }
        
        .explain-list-item {
            margin: 10px 0;
            padding-left: 8px;
            line-height: 1.7;
        }
        
        .explain-list-item::marker {
            color: var(--ui-highlight);
            font-weight: bold;
        }
        
        /* Loading State in Modal - LIGHT THEME */
        .explain-loading {
            text-align: center;
            padding: 60px 20px;
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        [data-theme="dark"] .explain-loading,
        [data-theme="solar"] .explain-loading {
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        .explain-loading .loader {
            width: 48px;
            height: 48px;
            border: 4px solid var(--border-color);
            border-top-color: var(--ui-highlight);
            border-radius: 50%;
            animation: spin 1s linear infinite;
            margin: 0 auto 20px;
        }
        
        [data-theme="dark"] .explain-loading .loader,
        [data-theme="solar"] .explain-loading .loader {
            border: 4px solid var(--border-color);
            border-top-color: var(--ui-highlight);
        }
        
        .explain-loading p {
            font-size: 1.125rem;
            color: var(--text-primary) !important;
            font-weight: 600;
            margin: 0 0 8px 0;
        }
        
        [data-theme="dark"] .explain-loading p,
        [data-theme="solar"] .explain-loading p {
            color: var(--text-primary) !important;
        }
        
        .explain-loading .explain-subtitle {
            font-size: 0.875rem;
            color: var(--text-tertiary) !important;
            font-weight: normal;
        }
        
        [data-theme="dark"] .explain-loading .explain-subtitle,
        [data-theme="solar"] .explain-loading .explain-subtitle {
            color: var(--text-secondary) !important;
        }
        
        /* Error State - LIGHT THEME */
        .explain-error {
            text-align: center;
            padding: 40px 20px;
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        [data-theme="dark"] .explain-error,
        [data-theme="solar"] .explain-error {
            background: var(--bg-primary) !important;
            background-color: var(--bg-primary) !important;
        }
        
        .explain-error .error-icon {
            font-size: 3rem;
            display: block;
            margin-bottom: 16px;
        }
        
        .explain-error h3 {
            color: var(--text-error) !important;
            margin: 0 0 12px 0;
        }
        
        .explain-error p {
            color: var(--text-tertiary) !important;
            margin-bottom: 20px;
        }
        
        [data-theme="dark"] .explain-error p,
        [data-theme="solar"] .explain-error p {
            color: var(--text-secondary) !important;
        }
        
        /* Mobile Responsive Modal */
        @media (max-width: 768px) {
            .explain-more-modal {
                padding: 0;
            }
            
            .explain-more-container {
                width: 100%;
                height: 100%;
                max-height: 100vh;
                border-radius: 0;
            }
            
            .explain-more-header {
                padding: 16px 20px;
            }
            
            .explain-title h2 {
                font-size: 1.25rem;
            }
            
            .explain-subtitle {
                display: none;
            }
            
            .explain-more-content {
                padding: 20px;
            }
            
            .deep-explanation {
                font-size: 0.875rem;
            }
            
            .explain-section-title {
                font-size: 1rem;
            }
        }
            /* ==========================================
           MOBILE RESPONSIVENESS (Max 768px)
           ========================================== */
        @media (max-width: 768px) {
            /* Main Workspace Constraints */
            .graphing-workspace, .workspace, .main-content { 
                width: 100%; 
                max-width: 100%; 
                margin: 0; 
                box-shadow: none; 
            }
            
            /* Content Area Constraints */
            #seo-content, .seo-content, .content-area { 
                padding: 30px 15px; 
                width: 100%;
                overflow: hidden;
            }
            
            #seo-content h1, .seo-content h1, .content-area h1 { 
                font-size: 1.75rem; 
                word-wrap: break-word; 
            }
            
            /* Force Grids to Single Column on Mobile */
            .feature-grid, 
            .use-case-section, 
            .related-tools,
            .calculator-grid,
            .tools-grid { 
                grid-template-columns: 1fr; 
                gap: 16px; 
            }
            
            /* Layout Adjustments */
            .graph-btn-grid, .btn-grid { 
                grid-template-columns: repeat(2, 1fr); 
            }
            
            .graph-form-grid, .form-grid { 
                grid-template-columns: 1fr; 
            }
            
            /* Author Card */
            .author-card { 
                flex-direction: column; 
                text-align: center; 
                padding: 20px 15px;
            }
            
            /* Footer Cleanup */
            .footer-content {
                display: grid;
                grid-template-columns: 1fr;
                gap: 24px;
                padding: 30px 20px;
                text-align: center;
            }
            
            .legal-disclaimer {
                padding: 20px 15px;
            }
            
            .legal-links {
                display: flex;
                flex-direction: column;
                gap: 12px;
            }
            
            /* Table scroll */
            .table-wrapper {
                margin: 16px 0;
            }
        }

        /* ==========================================
           EXTRA SMALL SCREENS (Max 480px)
           ========================================== */
        @media (max-width: 480px) {
            .graph-btn-grid, .btn-grid { 
                grid-template-columns: 1fr; 
            }
            
            .graph-eq-label, .eq-label {
                font-size: 0.75rem;
            }
            
            .ai-summary-box, .summary-box {
                padding: 16px;
            }
            
            .logo-title {
                font-size: 1.2rem !important;
            }
            
            h1 { font-size: 1.5rem; }
            h2 { font-size: 1.25rem; }
            h3 { font-size: 1.1rem; }
        }

        /* Theme-aware link colors – ensures readability across light/dark/solar themes */
        [data-theme="light"] .seo-content-section a,
        [data-theme="light"] main a:not(.nav-link):not(.footer-col a),
        [data-theme="light"] .legal-disclaimer a {
            color: #0066cc;
        }
        [data-theme="dark"] .seo-content-section a,
        [data-theme="dark"] main a:not(.nav-link):not(.footer-col a),
        [data-theme="dark"] .legal-disclaimer a {
            color: #5dade2;
        }
        [data-theme="solar"] .seo-content-section a,
        [data-theme="solar"] main a:not(.nav-link):not(.footer-col a),
        [data-theme="solar"] .legal-disclaimer a {
            color: #ffd700;
        }