:root {
            /* Brand palette for DrBuddy */
            --primary-blue: #0066CC; /* deep blue for trust */
            --secondary-blue: #0F2A44; /* dark navy for headings */
            --accent-teal: #00CEC9; /* friendly health accent */
            --medical-teal: #00B3AE; /* dedicated medical accent for borders/badges */
            --success-green: #00B894; /* success states */
            --muted-text: #636E72;
            --bg-light: #F8F9FA;
            --bg-white: #FFFFFF;
            --bg-muted: #F1F1F1;
            --border-light: #E9ECEF;
            --warning-amber: #FFC107;
            --warning-amber-dark: #856404;
            --shadow: 0 2px 10px rgba(15,42,68,0.08);
            --shadow-hover: 0 6px 24px rgba(15,42,68,0.12);
            /* text color tokens */
            --text-dark: #0b1a2b; /* deep text for high contrast */
            --bot-text: var(--secondary-blue); /* default bot response color */

            /* Backwards-compatible aliases (used in older CSS rules) */
            --accent-green: var(--success-green);
            --light-green: #55efc4;
            --text-light: var(--muted-text);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial;
            line-height: 1.6;
            color: var(--muted-text);
            background-color: var(--bg-light);
        }

        h1, h2, h3, h4 {
            font-family: 'Poppins', 'Inter', system-ui, sans-serif;
            color: var(--secondary-blue);
        }

        /* Brand logo in header */
        .brand {
            display: inline-flex;
            align-items: center;
            gap: 1rem;
            font-weight: 800;
            font-size: 2.2rem;
            /* allow the brand to occupy more space without breaking layout */
            justify-content: center;
        }

        .brand .logo {
            width: 720px; /* even bigger, stylish logo */
            height: auto;
            display: inline-block;
            vertical-align: middle;
            border-radius: 10px;
            transition: transform 0.45s cubic-bezier(0.22, 0.8, 0.28, 1), box-shadow 0.45s ease, filter 0.45s ease;
            box-shadow: 0 18px 50px rgba(15,42,68,0.18), 0 6px 18px rgba(0,0,0,0.08) inset;
            will-change: transform;
            background: linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.01));
            padding: 6px;
            filter: drop-shadow(0 6px 18px rgba(0,0,0,0.22));
        }

        /* hover effect: gentle float and glow */
        .brand .logo:hover {
            transform: translateY(-6px) scale(1.02) rotate(-0.5deg);
            box-shadow: 0 30px 80px rgba(15,42,68,0.24), 0 10px 30px rgba(0,0,0,0.12) inset;
            filter: drop-shadow(0 12px 22px rgba(0,0,0,0.24));
        }

        /* responsive scaling for larger viewports and smaller screens */
        @media (max-width: 1400px) {
            .brand .logo { width: 620px; }
            .brand { font-size: 2.1rem; }
        }

        @media (max-width: 1100px) {
            .brand .logo { width: 400px; }
            .brand { font-size: 2rem; }
        }

        @media (max-width: 760px) {
            .brand .logo { width: 240px; }
            .brand { font-size: 1.5rem; }
            .header { padding: 2rem 0; }
            .header h1 { font-size: 1.8rem; }
        }

        @media (max-width: 420px) {
            .brand .logo { width: 180px; }
            .brand { gap: 0.6rem; }
        }

        /* Visually hidden helper for screen readers */
        .sr-only {
            position: absolute;
            width: 1px;
            height: 1px;
            padding: 0;
            margin: -1px;
            overflow: hidden;
            clip: rect(0,0,0,0);
            white-space: nowrap;
            border: 0;
        }

        /* Header and Navigation */
        .header {
            background: linear-gradient(135deg, var(--primary-blue), var(--secondary-blue), var(--accent-green));
            /* reduce amplitude of the gradient travel and slow the cycle */
            background-size: 200% 200%;
            animation: backgroundShift 18s ease-in-out infinite;
            color: white;
            padding: 3rem 0;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .header::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="40" r="1.5" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="70" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="70" cy="80" r="2.5" fill="rgba(255,255,255,0.1)"/></svg>');
            animation: float 20s infinite linear;
        }

        @keyframes float {
            0% { transform: translateY(0px); }
            50% { transform: translateY(-10px); }
            100% { transform: translateY(0px); }
        }

        .header-content {
            position: relative;
            z-index: 1;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
        }

        .header h1 {
            font-size: 2.8rem;
            margin-bottom: 1rem;
            font-weight: 700;
            animation: fadeInScale 1s ease, textGlow 3s ease infinite;
        }

        .header .subtitle {
            font-size: 1.3rem;
            opacity: 0.9;
            margin-bottom: 2rem;
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }

        /* Prototype Button */
        .prototype-button-container {
            text-align: center;
            margin: 2rem 0;
        }

        .prototype-button {
            background: linear-gradient(45deg, var(--accent-green), var(--light-green));
            background-size: 200% 200%;
            animation: backgroundShift 4s ease infinite;
            color: white;
            padding: 1.2rem 2.5rem;
            border: none;
            border-radius: 50px;
            font-size: 1.1rem;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            box-shadow: 0 6px 20px rgba(0, 184, 148, 0.3);
            position: relative;
            overflow: hidden;
            text-decoration: none;
            display: inline-flex;
            align-items: center;
            gap: 0.8rem;
        }

        .prototype-button::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
            transition: left 0.6s;
        }

        .prototype-button:hover {
            transform: translateY(-3px) scale(1.05);
            box-shadow: 0 10px 30px rgba(0, 184, 148, 0.4);
        }

        .prototype-button:hover::before {
            left: 100%;
        }

        .prototype-button i {
            font-size: 1.3rem;
            animation: bounce 2s infinite;
        }

        @keyframes bounce {
            0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
            40% { transform: translateY(-5px); }
            60% { transform: translateY(-3px); }
        }

        /* Container and Layout */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 2rem;
        }

        .main-content {
            display: flex;
            flex-direction: column;
            gap: 3rem;
        }

        .section {
            background: var(--bg-white);
            border-radius: 15px;
            padding: 2.5rem;
            box-shadow: var(--shadow);
            animation: fadeInUp 0.6s ease;
            transition: all 0.4s ease;
            position: relative;
            overflow: hidden;
        }

        .section::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(0, 184, 148, 0.1), transparent);
            transition: left 0.8s ease;
        }

        .section:hover::before {
            left: 100%;
        }

        .section:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 30px rgba(0,0,0,0.15);
        }

        @keyframes fadeInUp {
            from { 
                opacity: 0; 
                transform: translateY(30px); 
            }
            to { 
                opacity: 1; 
                transform: translateY(0); 
            }
        }

        .section-title {
            color: var(--primary-blue);
            font-size: 2.2rem;
            margin-bottom: 2rem;
            display: flex;
            align-items: center;
            gap: 1rem;
            border-bottom: 3px solid var(--accent-green);
            padding-bottom: 1rem;
        }

        .section-title i {
            color: var(--accent-green);
            font-size: 2rem;
        }

        /* Architecture Diagram */
        .architecture-container {
            background: var(--bg-light);
            padding: 2rem;
            border-radius: 15px;
            margin: 2rem 0;
        }

        .architecture-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .arch-component {
            background: var(--bg-white);
            padding: 2rem;
            border-radius: 12px;
            text-align: center;
            box-shadow: var(--shadow);
            cursor: pointer;
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            border: 2px solid transparent;
            position: relative;
            overflow: hidden;
        }

        .arch-component::after {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: linear-gradient(45deg, transparent, rgba(0, 184, 148, 0.1), transparent);
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .arch-component:hover::after {
            opacity: 1;
        }

        .arch-component:hover {
            transform: translateY(-10px) scale(1.02);
            border-color: var(--accent-green);
            box-shadow: 0 15px 40px rgba(0, 184, 148, 0.3);
            animation: glow 2s ease infinite;
        }

        .arch-component i {
            font-size: 3rem;
            color: var(--primary-blue);
            margin-bottom: 1rem;
        }

        .arch-component h4 {
            color: var(--primary-blue);
            margin-bottom: 1rem;
            font-size: 1.2rem;
        }

        .arch-component p {
            color: var(--text-light);
            font-size: 0.9rem;
        }

        /* Features Grid */
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .feature-card {
            background: var(--bg-white);
            padding: 2rem;
            border-radius: 12px;
            box-shadow: var(--shadow);
            border-left: 5px solid var(--medical-teal);
            transition: transform 0.35s cubic-bezier(0.22, 0.8, 0.28, 1), box-shadow 0.35s ease;
            position: relative;
            overflow: hidden;
        }

        .feature-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: -5px;
            width: 5px;
            height: 100%;
            background: linear-gradient(to bottom, var(--medical-teal), var(--accent-green));
            transition: transform 0.35s ease, opacity 0.35s ease;
            transform-origin: left center;
        }

        /* Make the accent bar subtly grow on hover instead of filling the card */
        .feature-card:hover::before {
            transform: scaleX(1.6);
            opacity: 0.9;
        }

        .feature-card:hover {
            transform: translateY(-6px) scale(1.02);
            box-shadow: 0 12px 30px rgba(0, 206, 201, 0.15);
        }

        .feature-card h4 {
            color: var(--primary-blue);
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 0.8rem;
            font-size: 1.2rem;
        }

        .feature-card i {
            color: var(--accent-green);
            font-size: 1.3rem;
        }

        /* Technical Specs */
        .tech-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .tech-category {
            background: var(--bg-white);
            padding: 2rem;
            border-radius: 12px;
            box-shadow: var(--shadow);
            border-top: 4px solid var(--medical-teal);
        }

        .tech-category h4 {
            color: var(--primary-blue);
            margin-bottom: 1.5rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
            font-size: 1.2rem;
        }

        .tech-list {
            list-style: none;
        }

        .tech-list li {
            padding: 0.5rem 0;
            color: var(--text-light);
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .tech-list li::before {
            content: '✓';
            color: var(--accent-green);
            font-weight: bold;
        }

        /* Dashboard Charts */
        .dashboard-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .chart-container {
            background: var(--bg-white);
            padding: 2rem;
            border-radius: 15px;
            box-shadow: var(--shadow);
            height: 400px;
            position: relative;
            transition: all 0.3s ease;
            overflow: hidden;
        }

        .chart-container::before {
            content: '';
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: conic-gradient(from 0deg, transparent, rgba(0, 184, 148, 0.1), transparent);
            animation: rotate 10s linear infinite;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .chart-container:hover::before {
            opacity: 1;
        }

        @keyframes rotate {
            from {
                transform: rotate(0deg);
            }
            to {
                transform: rotate(360deg);
            }
        }

        .chart-container:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 35px rgba(0, 184, 148, 0.2);
        }

        .chart-title {
            color: var(--primary-blue);
            font-size: 1.3rem;
            margin-bottom: 1rem;
            text-align: center;
            font-weight: 600;
        }

        /* Implementation Timeline styles removed to reduce CSS size; timeline markup
           was removed from HTML. */

        /* Interactive Chatbot Section */
        .prototype-section {
            background: linear-gradient(135deg, var(--primary-blue), var(--secondary-blue));
            color: white;
            padding: 3rem 0;
            margin-top: 4rem;
            position: relative;
            overflow: hidden;
        }

        .prototype-section::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="40" r="1.5" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="70" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="70" cy="80" r="2.5" fill="rgba(255,255,255,0.1)"/></svg>');
            animation: float 20s infinite linear;
        }

        .prototype-content {
            position: relative;
            z-index: 1;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
        }

        .prototype-title {
            font-size: 2.5rem;
            margin-bottom: 1rem;
            text-align: center;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 1rem;
        }

        .prototype-subtitle {
            font-size: 1.2rem;
            opacity: 0.9;
            text-align: center;
            margin-bottom: 2rem;
        }

        /* Language Selector */
        .language-selector {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin: 2rem 0;
            flex-wrap: wrap;
        }

        .lang-btn {
            background: rgba(255,255,255,0.2);
            color: white;
            border: 2px solid rgba(255,255,255,0.3);
            padding: 0.7rem 1.5rem;
            border-radius: 25px;
            cursor: pointer;
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            backdrop-filter: blur(10px);
            position: relative;
            overflow: hidden;
        }

        .lang-btn::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            background: var(--accent-green);
            border-radius: 50%;
            transition: all 0.3s ease;
            transform: translate(-50%, -50%);
            z-index: -1;
        }

        .lang-btn:hover::before {
            width: 200%;
            height: 200%;
        }

        .lang-btn:hover, .lang-btn.active {
            border-color: var(--accent-green);
            transform: translateY(-3px) scale(1.05);
            box-shadow: 0 8px 20px rgba(0, 184, 148, 0.4);
        }

        .lang-btn.active {
            background: var(--accent-green);
        }

        /* Chatbot Interface */
        .chatbot-container {
            background: rgba(255,255,255,0.1);
            border-radius: 20px;
            padding: 2rem;
            margin: 2rem 0;
            backdrop-filter: blur(10px);
            max-width: 800px;
            margin: 2rem auto;
        }

        .chatbot-interface {
            background: var(--bg-white);
            border-radius: 20px;
            height: 600px;
            display: flex;
            flex-direction: column;
            box-shadow: 0 20px 60px rgba(0,0,0,0.2);
            overflow: hidden;
            animation: chatSlideIn 0.5s ease;
        }

        @keyframes chatSlideIn {
            from { 
                opacity: 0; 
                transform: translateY(30px) scale(0.95); 
            }
            to { 
                opacity: 1; 
                transform: translateY(0) scale(1); 
            }
        }

        .chat-header {
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            color: white;
            padding: 1.5rem;
            display: flex;
            align-items: center;
            gap: 1rem;
            border-radius: 20px 20px 0 0;
        }

        .bot-avatar {
            width: 50px;
            height: 50px;
            background: rgba(255,255,255,0.2);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            backdrop-filter: blur(10px);
        }

        .chat-header-info h3 {
            margin: 0;
            font-size: 1.2rem;
        }

        .chat-header-info p {
            margin: 0;
            font-size: 0.9rem;
            opacity: 0.9;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .status-indicator {
            width: 8px;
            height: 8px;
            background: var(--success-green);
            border-radius: 50%;
            animation: pulse 2s infinite;
        }

        @keyframes pulse {
            0% { opacity: 1; transform: scale(1); }
            50% { opacity: 0.7; transform: scale(1.1); }
            100% { opacity: 1; transform: scale(1); }
        }

        .chat-messages {
            flex: 1;
            padding: 1.5rem;
            overflow-y: auto;
            background: linear-gradient(to bottom, var(--bg-light), var(--bg-white));
            display: flex;
            flex-direction: column;
            gap: 1rem;
        }

        .chat-messages::-webkit-scrollbar {
            width: 6px;
        }

        .chat-messages::-webkit-scrollbar-track {
            background: var(--bg-muted);
            border-radius: 10px;
        }

        .chat-messages::-webkit-scrollbar-thumb {
            background: var(--accent-green);
            border-radius: 10px;
        }

        .message {
            max-width: 75%;
            padding: 1rem 1.5rem;
            border-radius: 20px;
            animation: messageSlide 0.4s ease;
            position: relative;
            word-wrap: break-word;
            line-height: 1.5;
        }

        @keyframes messageSlide {
            from { 
                opacity: 0; 
                transform: translateY(15px); 
            }
            to { 
                opacity: 1; 
                transform: translateY(0); 
            }
        }

        .message.bot {
            background: var(--bg-white);
            color: var(--bot-text);
            align-self: flex-start;
            border-bottom-left-radius: 5px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            border: 1px solid var(--border-light);
        }

        .message.user {
            background: linear-gradient(135deg, var(--primary-blue), var(--secondary-blue));
            color: white;
            align-self: flex-end;
            border-bottom-right-radius: 5px;
            box-shadow: 0 2px 10px rgba(0, 102, 204, 0.3);
        }

        .message-time {
            font-size: 0.7rem;
            opacity: 0.7;
            margin-top: 0.5rem;
            display: block;
        }

        .typing-indicator {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            padding: 1rem 1.5rem;
            background: var(--bg-white);
            border-radius: 20px;
            border-bottom-left-radius: 5px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            border: 1px solid var(--border-light);
            max-width: 75%;
            align-self: flex-start;
        }

        .typing-dots {
            display: flex;
            gap: 3px;
        }

        .typing-dot {
            width: 8px;
            height: 8px;
            background: var(--accent-green);
            border-radius: 50%;
            animation: typingAnimation 1.4s infinite;
        }

        .typing-dot:nth-child(2) {
            animation-delay: 0.2s;
        }

        .typing-dot:nth-child(3) {
            animation-delay: 0.4s;
        }

        @keyframes typingAnimation {
            0%, 60%, 100% { transform: translateY(0); }
            30% { transform: translateY(-10px); }
        }

        .quick-actions {
            padding: 1rem 1.5rem;
            background: var(--bg-light);
            border-top: 1px solid var(--border-light);
            display: flex;
            flex-wrap: wrap;
            gap: 0.8rem;
        }

        .quick-action {
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            color: white;
            padding: 0.6rem 1.2rem;
            border-radius: 25px;
            font-size: 0.85rem;
            cursor: pointer;
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            border: none;
            display: flex;
            align-items: center;
            gap: 0.5rem;
            font-weight: 500;
            position: relative;
            overflow: hidden;
        }

        .quick-action::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
            transition: left 0.5s ease;
        }

        .quick-action:hover::before {
            left: 100%;
        }

        .quick-action:hover {
            transform: translateY(-3px) scale(1.05);
            box-shadow: 0 8px 25px rgba(0, 184, 148, 0.5);
        }

        .quick-action i {
            transition: transform 0.3s ease;
        }

        .quick-action:hover i {
            transform: scale(1.2) rotate(10deg);
        }

        .chat-input-area {
            padding: 1.5rem;
            border-top: 1px solid var(--border-light);
            display: flex;
            gap: 1rem;
            background: var(--bg-white);
            border-radius: 0 0 20px 20px;
        }

        .chat-input {
            flex: 1;
            padding: 1rem 1.5rem;
            border: 2px solid var(--border-light);
            border-radius: 25px;
            outline: none;
            font-size: 1rem;
            transition: all 0.3s ease;
            background: var(--bg-light);
        }

        .chat-input:focus {
            border-color: var(--accent-green);
            background: white;
            box-shadow: 0 0 0 3px rgba(0, 184, 148, 0.1);
        }

        .send-btn {
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            color: white;
            border: none;
            padding: 1rem 1.5rem;
            border-radius: 50%;
            cursor: pointer;
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            display: flex;
            align-items: center;
            justify-content: center;
            width: 50px;
            height: 50px;
            font-size: 1.1rem;
            position: relative;
            overflow: hidden;
        }

        .send-btn::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            background: rgba(255,255,255,0.3);
            border-radius: 50%;
            transition: all 0.3s ease;
            transform: translate(-50%, -50%);
        }

        .send-btn:hover::before {
            width: 100%;
            height: 100%;
        }

        .send-btn:hover {
            transform: scale(1.15) rotate(15deg);
            box-shadow: 0 8px 25px rgba(0, 184, 148, 0.6);
        }

        .send-btn i {
            transition: transform 0.3s ease;
        }

        .send-btn:hover i {
            transform: translateX(2px);
        }

        .send-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
            transform: none;
        }

        /* Chat Controls */
        .chat-controls {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin-top: 1rem;
        }

        .chat-control-btn {
            background: rgba(255,255,255,0.2);
            color: white;
            border: 2px solid rgba(255,255,255,0.3);
            padding: 0.7rem 1.5rem;
            border-radius: 25px;
            cursor: pointer;
            transition: all 0.3s ease;
            backdrop-filter: blur(10px);
            font-size: 0.9rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .chat-control-btn:hover {
            background: rgba(255,255,255,0.3);
            transform: translateY(-2px);
        }

        /* Medical Disclaimer */
        .medical-disclaimer {
            background: rgba(255, 193, 7, 0.1);
            border: 1px solid var(--warning-amber);
            border-radius: 15px;
            padding: 1rem 1.5rem;
            margin: 1rem 0;
            text-align: center;
            color: var(--warning-amber-dark);
            font-size: 0.9rem;
        }

        .medical-disclaimer i {
            color: var(--warning-amber);
            margin-right: 0.5rem;
        }

        /* Feedback System */
        .message-feedback {
            display: flex;
            gap: 0.5rem;
            margin-top: 0.5rem;
            opacity: 0.7;
        }

        .feedback-btn {
            background: none;
            border: none;
            cursor: pointer;
            font-size: 0.8rem;
            color: var(--text-light);
            transition: all 0.3s ease;
            padding: 0.2rem 0.5rem;
            border-radius: 10px;
        }

        .feedback-btn:hover {
            background: var(--bg-light);
            color: var(--accent-green);
        }

        .feedback-btn.active {
            color: var(--accent-green);
        }

        /* Branding */
        /* Floating AI Assistant */
        .ai-assistant-widget {
            position: fixed;
            bottom: 20px;
            right: 20px;
            z-index: 1001;
        }

        .ai-button {
            width: 60px;
            height: 60px;
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            border: none;
            border-radius: 50%;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
            box-shadow: 0 4px 20px rgba(0, 184, 148, 0.4);
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            display: flex;
            align-items: center;
            justify-content: center;
            /* idle: subtle, non-distracting */
            animation: glow 6s ease infinite;
            position: relative;
            overflow: hidden;
        }

        .ai-button::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: conic-gradient(from 0deg, transparent, rgba(255,255,255,0.3), transparent);
            border-radius: 50%;
            animation: rotate 3s linear infinite;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .ai-button:hover::before {
            opacity: 1;
        }

        .ai-button:hover {
            transform: scale(1.2) rotate(10deg);
            box-shadow: 0 8px 30px rgba(0, 184, 148, 0.8);
        }

        .ai-button i {
            transition: transform 0.3s ease;
            z-index: 1;
        }

        .ai-button:hover i {
            transform: scale(1.1);
        }

        .ai-chat-widget {
            position: absolute;
            bottom: 80px;
            right: 0;
            width: 350px;
            /* responsive height to avoid double scroll and clipping */
            height: min(500px, calc(100vh - 140px));
            background: white;
            border-radius: 20px;
            box-shadow: 0 10px 40px rgba(0,0,0,0.2);
            display: none;
            flex-direction: column;
            overflow: hidden;
            animation: slideUp 0.3s ease;
        }

        /* Respect user motion preferences */
        @media (prefers-reduced-motion: reduce) {
            *, *::before, *::after { animation: none !important; transition: none !important; }
            .prototype-button, .arch-component, .feature-card, .chart-container, .chatbot-interface { box-shadow: var(--shadow); transform: none !important; }
            .header { background-size: 100% 100%; }
            .header::before, .prototype-section::before { animation: none !important; }
        }

        .ai-chat-widget.active {
            display: flex;
        }

        @keyframes slideUp {
            from {
                opacity: 0;
                transform: translateY(20px) scale(0.9);
            }
            to {
                opacity: 1;
                transform: translateY(0) scale(1);
            }
        }

        .ai-chat-header {
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            color: white;
            padding: 1rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }

        .ai-chat-header h4 {
            margin: 0;
            font-size: 1.1rem;
        }

        .ai-close-btn {
            background: none;
            border: none;
            color: white;
            font-size: 1.2rem;
            cursor: pointer;
            padding: 0.2rem;
            border-radius: 50%;
            transition: background 0.3s ease;
        }

        .ai-close-btn:hover {
            background: rgba(255,255,255,0.2);
        }

        .ai-chat-messages {
            flex: 1;
            padding: 1rem;
            overflow-y: auto;
            background: var(--bg-light);
        }

        .ai-message {
            background: white;
            padding: 0.8rem 1rem;
            border-radius: 15px;
            margin-bottom: 0.8rem;
            box-shadow: 0 2px 5px rgba(0,0,0,0.1);
            color: var(--text-dark);
            font-size: 0.9rem;
            line-height: 1.4;
        }

        .ai-chat-input {
            padding: 1rem;
            border-top: 1px solid var(--border-light);
            display: flex;
            gap: 0.5rem;
        }

        .ai-input {
            flex: 1;
            padding: 0.8rem;
            border: 1px solid var(--border-light);
            border-radius: 20px;
            outline: none;
            font-size: 0.9rem;
        }

        .ai-send-btn {
            background: var(--accent-green);
            color: white;
            border: none;
            padding: 0.8rem 1rem;
            border-radius: 50%;
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .ai-send-btn:hover {
            background: var(--light-green);
            transform: scale(1.1);
        }

        .healthbot-branding {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background: linear-gradient(135deg, var(--primary-blue), var(--success-green));
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.8rem;
    cursor: default;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
    display: flex;
    align-items: center;
    gap: 8px;
}

.kuse-branding {
            position: fixed;
            bottom: 20px;
            left: 20px;
            background: rgba(255, 255, 255, 0.95);
            padding: 10px 15px;
            border-radius: 25px;
            box-shadow: var(--shadow);
            font-size: 0.9rem;
            color: var(--text-dark);
            display: flex;
            align-items: center;
            gap: 8px;
            cursor: pointer;
            transition: all 0.3s ease;
            backdrop-filter: blur(10px);
            z-index: 1000;
        }

        .kuse-branding:hover {
            background: var(--accent-green);
            color: white;
            transform: translateY(-2px);
            box-shadow: var(--shadow-hover);
        }

        .kuse-branding svg {
            height: 1.2em;
            transition: all 0.3s ease;
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .container {
                padding: 1rem;
            }

            .header h1 {
                font-size: 2.2rem;
            }

            .section-title {
                font-size: 1.8rem;
            }

            .architecture-grid,
            .features-grid,
            .dashboard-grid,
            .tech-grid {
                grid-template-columns: 1fr;
            }

            .timeline::before {
                left: 20px;
            }

            .timeline-item {
                width: calc(100% - 40px);
                left: 40px !important;
                text-align: left !important;
                padding-left: 1rem !important;
                padding-right: 0 !important;
            }

            .timeline-item::before {
                left: -32px !important;
            }

            .chatbot-interface {
                height: 500px;
            }

            .prototype-title {
                font-size: 2rem;
                flex-direction: column;
            }

            .chatbot-container {
                padding: 1rem;
                margin: 1rem 0;
            }

            .message {
                max-width: 85%;
            }

            .quick-actions {
                justify-content: center;
            }

            .language-selector {
                gap: 0.5rem;
            }

            .lang-btn {
                padding: 0.5rem 1rem;
                font-size: 0.9rem;
            }
        }

        /* Modern Animations & Effects */
        @keyframes fadeInScale {
            from {
                opacity: 0;
                transform: scale(0.8) translateY(30px);
            }
            to {
                opacity: 1;
                transform: scale(1) translateY(0);
            }
        }

        @keyframes slideInLeft {
            from {
                opacity: 0;
                transform: translateX(-50px);
            }
            to {
                opacity: 1;
                transform: translateX(0);
            }
        }

        @keyframes slideInRight {
            from {
                opacity: 0;
                transform: translateX(50px);
            }
            to {
                opacity: 1;
                transform: translateX(0);
            }
        }

        @keyframes glow {
            0%, 100% {
                box-shadow: 0 0 20px rgba(0, 184, 148, 0.3);
            }
            50% {
                box-shadow: 0 0 30px rgba(0, 184, 148, 0.6);
            }
        }

        @keyframes morphing {
            0%, 100% {
                border-radius: 15px;
            }
            50% {
                border-radius: 25px;
            }
        }

        @keyframes textGlow {
            0%, 100% {
                text-shadow: 0 0 10px rgba(0, 184, 148, 0.5);
            }
            50% {
                text-shadow: 0 0 20px rgba(0, 184, 148, 0.8);
            }
        }

        @keyframes backgroundShift {
            0% { background-position: 0% 50%; }
            50% { background-position: 100% 50%; }
            100% { background-position: 0% 50%; }
        }

        /* Smooth scrolling */
        html {
            scroll-behavior: smooth;
        }

        /* When reducing animations (during scroll), avoid heavy shadows only */

        /* Removed scroll shadow reduction to avoid visual popping */

        /* Scroll Animation Classes */
        .animate-in {
            animation-play-state: running !important;
        }

        .fade-in-up {
            animation: fadeInUp 0.8s ease forwards;
        }

        .fade-in-left {
            animation: slideInLeft 0.8s ease forwards;
        }

        .fade-in-right {
            animation: slideInRight 0.8s ease forwards;
        }

        .scale-in {
            animation: fadeInScale 0.6s ease forwards;
        }

        /* Magnetic Button Effect */
        .magnetic-btn {
            transition: transform 0.2s ease;
        }

        /* Glowing Text Effect */
        .glow-text {
            animation: textGlow 3s ease infinite;
        }

        /* Floating Animation */
        .floating {
            animation: float 6s ease-in-out infinite;
        }

        @keyframes floatSlow {
            0%, 100% {
                transform: translateY(0px);
            }
            50% {
                transform: translateY(-15px);
            }
        }

        /* Pulse Animation for Important Elements */
        .pulse-glow {
            animation: pulse 2s infinite, glow 3s ease infinite;
        }

        /* Floating branding button (bottom-right) */
        .floating-brand-btn {
            position: fixed;
            left: 20px;
            bottom: 24px;
            display: inline-flex;
            align-items: center;
            gap: 0.6rem;
            background: linear-gradient(135deg, var(--primary-blue), var(--accent-teal));
            color: white;
            border: none;
            padding: 0.6rem 0.9rem;
            border-radius: 999px;
            box-shadow: 0 14px 40px rgba(15,42,68,0.18);
            cursor: pointer;
            font-weight: 600;
            font-family: 'Poppins', Inter, sans-serif;
            transition: transform 0.18s ease, box-shadow 0.18s ease, padding 0.18s ease;
            z-index: 1200;
        }

        .floating-brand-btn .brand-mark {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: rgba(255,255,255,0.12);
            backdrop-filter: blur(6px);
            font-weight: 700;
        }

        .floating-brand-btn .brand-label {
            display: inline-block;
            transform-origin: left center;
            transition: transform 0.18s ease, opacity 0.18s ease;
        }

        .floating-brand-btn:hover {
            transform: translateY(-4px) scale(1.02);
            box-shadow: 0 22px 60px rgba(15,42,68,0.22);
        }

        .floating-brand-btn:focus {
            outline: 3px solid rgba(0,206,201,0.18);
            outline-offset: 4px;
        }

        /* Compact on very small screens */
        @media (max-width: 420px) {
            .floating-brand-btn { padding: 0.4rem 0.5rem; gap: 0.4rem; }
            .floating-brand-btn .brand-label { display: none; }
        }

        /* Overview metrics */
        .overview-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin-top: 2rem;
        }

        .overview-card {
            background: linear-gradient(135deg, var(--bg-light), var(--bg-white));
            padding: 2rem;
            border-radius: 15px;
            border-left: 4px solid var(--accent-green);
            transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
            position: relative;
            overflow: hidden;
        }

        .overview-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: linear-gradient(45deg, transparent, rgba(0, 184, 148, 0.1), transparent);
            transform: translateX(-100%);
            transition: transform 0.6s ease;
        }

        .overview-card:hover::before {
            transform: translateX(100%);
        }

        .overview-card:hover {
            transform: translateY(-8px) scale(1.02);
            box-shadow: 0 15px 40px rgba(0, 184, 148, 0.3);
        }

        .overview-card h3 {
            color: var(--primary-blue);
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
            transition: transform 0.3s ease;
        }

        .overview-card:hover h3 {
            transform: scale(1.05);
        }

        .metric-highlight {
            background: linear-gradient(135deg, var(--accent-green), var(--light-green));
            color: white;
            padding: 0.25rem 0.75rem;
            border-radius: 20px;
            font-weight: bold;
            display: inline-block;
            margin: 0.5rem 0;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
        }

        .metric-highlight::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
            transition: left 0.5s ease;
        }

        .metric-highlight:hover::before {
            left: 100%;
        }

        .metric-highlight:hover {
            transform: scale(1.1);
            box-shadow: 0 4px 15px rgba(0, 184, 148, 0.4);
        }