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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
            background: linear-gradient(135deg, #0a0a0f 0%, #1a1a2e 50%, #16213e 100%);
            min-height: 100vh;
            color: #e0e0e0;
            padding: 20px;
            overflow-x: hidden;
        }

        .container {
            max-width: 100%;
            margin: 0 auto;
        }

        header {
            background: rgba(255, 255, 255, 0.05);
            backdrop-filter: blur(10px);
            border-radius: 16px;
            padding: 20px 30px;
            margin-bottom: 20px;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }

        h1 {
            font-size: 28px;
            background: linear-gradient(135deg, #4facfe, #00f2fe);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            margin-bottom: 8px;
        }

        .subtitle {
            color: #a0a0a0;
            font-size: 14px;
        }

        .timeline-wrapper {
            background: rgba(255, 255, 255, 0.05);
            backdrop-filter: blur(10px);
            border-radius: 16px;
            border: 1px solid rgba(255, 255, 255, 0.1);
            overflow: hidden;
            margin-bottom: 20px;
        }

        .timeline-header {
            padding: 25px 30px;
            background: linear-gradient(135deg, rgba(5, 150, 105, 0.15), rgba(4, 120, 87, 0.15));
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }

        .timeline-title {
            font-size: 32px;
            margin-bottom: 10px;
            color: #fff;
        }

        .timeline-description {
            color: #c0c0c0;
            line-height: 1.6;
            font-size: 15px;
        }

        .timeline-container {
            padding: 40px 20px;
            overflow-x: auto;
            overflow-y: hidden;
        }

        .timeline {
            position: relative;
            min-width: 2000px;
            height: 400px;
        }

        .timeline-axis {
            position: absolute;
            top: 50%;
            left: 0;
            right: 0;
            height: 4px;
            background: linear-gradient(90deg, #059669, #4facfe, #a855f7);
            border-radius: 2px;
        }

        .era {
            position: absolute;
            top: 50%;
            transform: translateY(-50%);
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .era-marker {
            width: 24px;
            height: 24px;
            background: linear-gradient(135deg, #059669, #047857);
            border: 3px solid rgba(255, 255, 255, 0.3);
            border-radius: 50%;
            position: relative;
            z-index: 2;
            box-shadow: 0 0 20px rgba(5, 150, 105, 0.5);
        }

        .era:hover .era-marker {
            transform: scale(1.3);
            box-shadow: 0 0 30px rgba(5, 150, 105, 0.8);
            border-color: #00f2fe;
        }

        .era-label {
            position: absolute;
            top: -60px;
            left: 50%;
            transform: translateX(-50%);
            white-space: nowrap;
            background: rgba(0, 0, 0, 0.8);
            padding: 8px 16px;
            border-radius: 8px;
            border: 1px solid rgba(255, 255, 255, 0.2);
            font-size: 13px;
            font-weight: 600;
            color: #4facfe;
        }

        .era-year {
            position: absolute;
            top: 40px;
            left: 50%;
            transform: translateX(-50%);
            font-size: 14px;
            font-weight: 700;
            color: #fff;
        }

        .era-discoverer {
            position: absolute;
            top: 65px;
            left: 50%;
            transform: translateX(-50%);
            font-size: 11px;
            color: #a0a0a0;
            white-space: nowrap;
        }

        .era.active .era-marker {
            background: linear-gradient(135deg, #4facfe, #00f2fe);
            transform: scale(1.5);
            box-shadow: 0 0 40px rgba(79, 172, 254, 1);
        }

        .content-panel {
            display: none;
            padding: 30px;
            background: rgba(0, 0, 0, 0.3);
            border-top: 1px solid rgba(255, 255, 255, 0.1);
        }

        .content-panel.active {
            display: block;
            animation: slideDown 0.4s ease;
        }

        @keyframes slideDown {
            from {
                opacity: 0;
                transform: translateY(-20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .panel-header {
            margin-bottom: 30px;
            text-align: center;
        }

        .panel-title {
            font-size: 28px;
            color: #00f2fe;
            margin-bottom: 10px;
        }

        .panel-meta {
            display: flex;
            gap: 30px;
            justify-content: center;
            flex-wrap: wrap;
            margin-top: 15px;
        }

        .meta-item {
            background: rgba(255, 255, 255, 0.05);
            padding: 10px 20px;
            border-radius: 8px;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }

        .meta-label {
            font-size: 11px;
            color: #a0a0a0;
            text-transform: uppercase;
            letter-spacing: 1px;
            margin-bottom: 5px;
        }

        .meta-value {
            font-size: 15px;
            color: #fff;
            font-weight: 600;
        }

        .sections-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
            gap: 25px;
            margin-bottom: 30px;
        }

        .content-section {
            background: rgba(255, 255, 255, 0.05);
            padding: 20px;
            border-radius: 12px;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }

        .section-title {
            font-size: 18px;
            color: #4facfe;
            margin-bottom: 12px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .section-text {
            color: #d0d0d0;
            line-height: 1.7;
            font-size: 14px;
        }

        .section-text p {
            margin-bottom: 12px;
        }

        .comparison-box {
            background: rgba(79, 172, 254, 0.05);
            border: 1px solid rgba(79, 172, 254, 0.3);
            border-radius: 12px;
            padding: 20px;
            margin-bottom: 25px;
        }

        .comparison-title {
            font-size: 18px;
            color: #4facfe;
            margin-bottom: 15px;
            text-align: center;
        }

        .comparison-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
        }

        .comparison-side {
            padding: 15px;
            background: rgba(0, 0, 0, 0.3);
            border-radius: 8px;
        }

        .comparison-side h4 {
            color: #fbbf24;
            font-size: 14px;
            margin-bottom: 10px;
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        .comparison-side p {
            color: #d0d0d0;
            font-size: 13px;
            line-height: 1.6;
        }

        .sources-list {
            background: rgba(0, 0, 0, 0.3);
            padding: 20px;
            border-radius: 12px;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }

        .sources-list h3 {
            color: #4facfe;
            font-size: 16px;
            margin-bottom: 12px;
        }

        .sources-list ul {
            list-style: none;
            padding: 0;
        }

        .sources-list li {
            padding: 8px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
            color: #c0c0c0;
            font-size: 13px;
        }

        .sources-list li:last-child {
            border-bottom: none;
        }

        .action-bar {
            display: flex;
            gap: 15px;
            justify-content: center;
            padding: 25px;
            background: rgba(0, 0, 0, 0.2);
            border-top: 1px solid rgba(255, 255, 255, 0.1);
        }

        .nav-btn {
            padding: 12px 28px;
            border: none;
            border-radius: 10px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            font-size: 14px;
            background: rgba(255, 255, 255, 0.1);
            color: #4facfe;
            border: 2px solid #4facfe;
        }

        .nav-btn:hover {
            background: #4facfe;
            color: white;
            transform: translateY(-2px);
        }

        .close-btn {
            background: linear-gradient(135deg, #f093fb, #f5576c);
            color: white;
            border: none;
        }

        .close-btn:hover {
            box-shadow: 0 6px 20px rgba(240, 147, 251, 0.4);
        }

        .loading {
            text-align: center;
            padding: 60px 20px;
            color: #4facfe;
            font-size: 18px;
        }

        .error {
            text-align: center;
            padding: 60px 20px;
            color: #ef4444;
            font-size: 16px;
        }