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

        :root {
            --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
            --dark-bg: #000;
            --darker-bg: #0a0a0a;
            --card-bg: rgba(255, 255, 255, 0.05);
            --border-color: rgba(255, 255, 255, 0.1);
            --text-primary: #fff;
            --text-secondary: rgba(255, 255, 255, 0.8);
            --accent-color: #667eea;
            --warning-color: #ff6b6b;
            --success-color: #4ecdc4;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: var(--dark-bg);
            color: var(--text-primary);
            line-height: 1.6;
            overflow-x: hidden;
        }

        /* Animated Background */
        .bg-animation {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            pointer-events: none;
            z-index: -1;
        }

        .floating-shapes {
            position: absolute;
            width: 100%;
            height: 100%;
        }

        .shape {
            position: absolute;
            background: var(--primary-gradient);
            border-radius: 50%;
            opacity: 0.08;
            animation: float 25s infinite ease-in-out;
        }

        .shape:nth-child(1) { width: 100px; height: 100px; top: 10%; left: 10%; animation-delay: 0s; }
        .shape:nth-child(2) { width: 150px; height: 150px; top: 70%; left: 85%; animation-delay: 8s; }
        .shape:nth-child(3) { width: 80px; height: 80px; top: 40%; left: 20%; animation-delay: 16s; }
        .shape:nth-child(4) { width: 120px; height: 120px; top: 20%; left: 75%; animation-delay: 24s; }

        @keyframes float {
            0%, 100% { transform: translateY(0px) rotate(0deg); }
            33% { transform: translateY(-40px) rotate(120deg); }
            66% { transform: translateY(30px) rotate(240deg); }
        }

        /* Navigation */
        .nav-header {
            position: fixed;
            top: 0;
            width: 100%;
            background: rgba(0, 0, 0, 0.8);
            backdrop-filter: blur(20px);
            z-index: 1000;
            padding: 1rem 0;
            border-bottom: 1px solid var(--border-color);
        }

        .nav-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 1rem;
            font-size: 1.2rem;
            font-weight: 600;
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .progress-bar {
            height: 3px;
            background: var(--primary-gradient);
            width: 0%;
            position: absolute;
            bottom: 0;
            left: 0;
            transition: width 0.3s ease;
        }

        /* Slide Container */
        .presentation-container {
            position: relative;
            height: 100vh;
            overflow: hidden;
        }

        .slide {
            position: absolute;
            width: 100%;
            height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            opacity: 0;
            transform: translateX(100px);
            transition: all 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            padding: 2rem;
        }

        .slide.active {
            opacity: 1;
            transform: translateX(0);
        }

        .slide.prev {
            transform: translateX(-100px);
        }

        .slide-content {
            max-width: 1000px;
            text-align: center;
            position: relative;
            z-index: 2;
        }

        /* Slide Styles */
        .slide-title {
            font-size: clamp(2.5rem, 6vw, 4.5rem);
            font-weight: 800;
            margin-bottom: 2rem;
            background: linear-gradient(135deg, #fff 0%, #667eea 50%, #764ba2 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            animation: textShimmer 3s ease-in-out infinite;
        }

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

        .slide-subtitle {
            font-size: clamp(1.2rem, 3vw, 1.8rem);
            margin-bottom: 3rem;
            opacity: 0.9;
            font-weight: 300;
        }

        .slide-text {
            font-size: clamp(1rem, 2vw, 1.3rem);
            line-height: 1.8;
            opacity: 0.85;
            margin-bottom: 2rem;
            text-align: left;
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }

        /* Special Slide Styles */
        .intro-slide {
            background: radial-gradient(ellipse at center, rgba(102, 126, 234, 0.15) 0%, rgba(0, 0, 0, 1) 70%);
        }

        .concept-slide {
            background: linear-gradient(135deg, rgba(255, 107, 107, 0.1) 0%, rgba(0, 0, 0, 1) 100%);
        }

        .reality-slide {
            background: linear-gradient(135deg, rgba(78, 205, 196, 0.1) 0%, rgba(0, 0, 0, 1) 100%);
        }

        .analogy-slide {
            background: linear-gradient(135deg, rgba(240, 147, 251, 0.1) 0%, rgba(0, 0, 0, 1) 100%);
        }

        .conclusion-slide {
            background: radial-gradient(ellipse at center, rgba(102, 126, 234, 0.2) 0%, rgba(118, 75, 162, 0.1) 50%, rgba(0, 0, 0, 1) 100%);
        }

        /* Icon Styles */
        .slide-icon {
            width: 100px;
            height: 100px;
            margin: 0 auto 2rem;
            background: var(--primary-gradient);
            border-radius: 25px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2.5rem;
            box-shadow: 0 20px 40px rgba(102, 126, 234, 0.3);
            animation: iconFloat 4s ease-in-out infinite;
        }

        @keyframes iconFloat {
            0%, 100% { transform: translateY(0px) scale(1); }
            50% { transform: translateY(-10px) scale(1.05); }
        }

        /* Quote Style */
        .quote {
            background: var(--card-bg);
            border-left: 4px solid var(--accent-color);
            padding: 2rem;
            margin: 2rem 0;
            border-radius: 15px;
            backdrop-filter: blur(15px);
            font-style: italic;
            font-size: 1.1rem;
            border: 1px solid var(--border-color);
        }

        /* Highlight Boxes */
        .highlight-box {
            background: var(--card-bg);
            border: 1px solid var(--border-color);
            border-radius: 20px;
            padding: 2rem;
            margin: 2rem 0;
            backdrop-filter: blur(15px);
            position: relative;
            overflow: hidden;
        }

        .highlight-box::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 3px;
            background: var(--primary-gradient);
        }

        .warning-box {
            border-color: rgba(255, 107, 107, 0.3);
        }

        .warning-box::before {
            background: linear-gradient(135deg, #ff6b6b 0%, #ff8e53 100%);
        }

        .success-box {
            border-color: rgba(78, 205, 196, 0.3);
        }

        .success-box::before {
            background: linear-gradient(135deg, #4ecdc4 0%, #44a08d 100%);
        }

        /* Navigation Controls */
        .nav-controls {
            position: fixed;
            bottom: 2rem;
            left: 50%;
            transform: translateX(-50%);
            display: flex;
            gap: 1rem;
            z-index: 1000;
        }

        .nav-btn {
            padding: 0.8rem 1.5rem;
            background: var(--card-bg);
            border: 1px solid var(--border-color);
            border-radius: 50px;
            color: var(--text-primary);
            cursor: pointer;
            transition: all 0.3s ease;
            backdrop-filter: blur(15px);
            font-weight: 500;
        }

        .nav-btn:hover {
            background: var(--primary-gradient);
            transform: translateY(-2px);
            box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
        }

        .nav-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }

        .nav-btn:disabled:hover {
            transform: none;
            box-shadow: none;
            background: var(--card-bg);
        }

        /* Slide Indicators */
        .slide-indicators {
            position: fixed;
            right: 2rem;
            top: 50%;
            transform: translateY(-50%);
            display: flex;
            flex-direction: column;
            gap: 1rem;
            z-index: 1000;
        }

        .indicator {
            width: 12px;
            height: 12px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.3);
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .indicator.active {
            background: var(--accent-color);
            box-shadow: 0 0 15px rgba(102, 126, 234, 0.5);
        }

        /* Statistics */
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 2rem;
            margin: 2rem 0;
        }

        .stat-item {
            background: var(--card-bg);
            padding: 2rem;
            border-radius: 15px;
            border: 1px solid var(--border-color);
            text-align: center;
            transition: all 0.3s ease;
        }

        .stat-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(102, 126, 234, 0.2);
        }

        .stat-number {
            font-size: 2.5rem;
            font-weight: 700;
            background: var(--primary-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .stat-label {
            margin-top: 0.5rem;
            opacity: 0.8;
        }

        /* Mobile Optimization */
        @media (max-width: 768px) {
            .slide {
                padding: 1rem;
                height: 100vh;
                overflow-y: auto;
            }
            
            .slide-content {
                padding: 1rem;
                max-width: 100%;
                overflow: hidden;
            }
            
            .slide-text {
                font-size: 1rem;
                text-align: center;
                word-wrap: break-word;
                overflow-wrap: break-word;
            }
            
            .slide-content h1 {
                font-size: 1.8rem !important;
                line-height: 1.3;
                margin-bottom: 1rem;
            }
            
            .slide-content h2 {
                font-size: 1.4rem !important;
                line-height: 1.3;
                margin-bottom: 0.8rem;
            }
            
            .slide-content p {
                font-size: 0.9rem;
                line-height: 1.5;
                margin-bottom: 0.8rem;
            }
            
            .nav-controls {
                flex-direction: row;
                bottom: 1rem;
                gap: 0.5rem;
                flex-wrap: wrap;
                justify-content: center;
            }
            
            .nav-btn {
                padding: 0.6rem 1rem;
                font-size: 0.9rem;
                flex: 1;
                max-width: 100px;
                min-width: 80px;
            }
            
            .nav-btn#homeBtn {
                order: -1;
                background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
                border-color: var(--accent-color);
            }
            
            .slide-indicators {
                display: none;
            }
            
            .stats-grid {
                grid-template-columns: 1fr;
                gap: 1rem;
            }
            
            .nav-container {
                padding: 0 1rem;
            }
            
            .logo {
                font-size: 1rem;
            }
            
            .autoplay-indicator {
                top: 0.5rem;
                right: 1rem;
                font-size: 0.8rem;
                padding: 0.3rem 0.8rem;
            }
        }

        /* Tablet Optimization */
        @media (max-width: 1024px) and (min-width: 769px) {
            .slide-content {
                padding: 2rem;
                max-width: 90%;
            }
            
            .slide-content h1 {
                font-size: 2.2rem;
            }
            
            .slide-content h2 {
                font-size: 1.8rem;
            }
            
            .nav-controls {
                bottom: 1.5rem;
            }
        }

        /* Extra small screens */
        @media (max-width: 480px) {
            .slide {
                padding: 0.5rem;
            }
            
            .slide-content {
                padding: 0.5rem;
            }
            
            .slide-content h1 {
                font-size: 1.5rem !important;
            }
            
            .slide-content h2 {
                font-size: 1.2rem !important;
            }
            
            .nav-controls {
                bottom: 0.5rem;
                left: 1rem;
                right: 1rem;
                transform: none;
                width: auto;
            }
            
            .nav-btn {
                font-size: 0.8rem;
                padding: 0.5rem 0.6rem;
                min-width: 70px;
                max-width: 90px;
            }
            
            .nav-btn#homeBtn {
                background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            }
        }

        /* Auto-play indicator */
        .autoplay-indicator {
            position: fixed;
            top: 1rem;
            right: 2rem;
            background: var(--card-bg);
            padding: 0.5rem 1rem;
            border-radius: 25px;
            border: 1px solid var(--border-color);
            backdrop-filter: blur(15px);
            font-size: 0.9rem;
            z-index: 1000;
        }

        .pause-btn {
            background: none;
            border: none;
            color: var(--accent-color);
            cursor: pointer;
            margin-left: 0.5rem;
            font-weight: 600;
        }

        /* Smooth animations for content */
        .slide-content > * {
            opacity: 0;
            transform: translateY(30px);
            animation: slideInContent 0.8s ease-out forwards;
        }

        .slide-content > *:nth-child(1) { animation-delay: 0.2s; }
        .slide-content > *:nth-child(2) { animation-delay: 0.4s; }
        .slide-content > *:nth-child(3) { animation-delay: 0.6s; }
        .slide-content > *:nth-child(4) { animation-delay: 0.8s; }

        @keyframes slideInContent {
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        /* Pause animation when not active */
        .slide:not(.active) .slide-content > * {
            animation-play-state: paused;
        }