/* roulang page: index */
:root {
            --bg-dark: #0F1416;
            --bg-dark-elevated: #161F24;
            --bg-canvas: #F8FAFC;
            --bg-surface: #FFFFFF;
            --primary-vigor: #00C853;
            --primary-vigor-deep: #059669;
            --accent-kinetic: #FF6D00;
            --accent-kinetic-soft: #F97316;
            --text-main: #0F172A;
            --text-secondary: #334155;
            --text-muted: #64748B;
            --text-on-dark: #F1F5F9;
            --border-subtle: rgba(15, 23, 42, 0.08);
            --border-dark: rgba(255, 255, 255, 0.1);
            --radius-card: 16px;
            --radius-btn: 12px;
            --shadow-card: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
            --shadow-card-hover: 0 20px 25px -5px rgba(0, 200, 83, 0.12), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
            --transition-base: all 0.28s cubic-bezier(0.16, 1, 0.3, 1);
        }

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

        html, body {
            width: 100%;
            max-width: 100vw;
            overflow-x: hidden;
            background-color: var(--bg-canvas);
            color: var(--text-main);
            font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            line-height: 1.65;
            -webkit-font-smoothing: antialiased;
        }

        a {
            color: inherit;
            text-decoration: none;
            transition: var(--transition-base);
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        button, input, select, textarea {
            font-family: inherit;
            outline: none;
        }

        .container-custom {
            width: 100%;
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
            padding-left: 1.25rem;
            padding-right: 1.25rem;
        }

        /* Dual-row Header */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 50;
            width: 100%;
            box-shadow: 0 4px 20px rgba(15, 20, 22, 0.06);
        }

        .top-utility-bar {
            background-color: var(--bg-dark);
            color: #CBD5E1;
            min-height: 36px;
            font-size: 0.78rem;
            border-bottom: 1px solid rgba(255, 255, 255, 0.07);
            display: flex;
            align-items: center;
        }

        .main-nav-bar {
            background: rgba(255, 255, 255, 0.94);
            backdrop-filter: blur(14px);
            -webkit-backdrop-filter: blur(14px);
            height: 72px;
            border-bottom: 1px solid var(--border-subtle);
            display: flex;
            align-items: center;
        }

        .nav-link-item {
            position: relative;
            display: inline-flex;
            align-items: center;
            min-height: 44px;
            padding: 0 0.65rem;
            font-size: 0.92rem;
            font-weight: 500;
            color: var(--text-secondary);
            border-radius: 8px;
        }

        .nav-link-item:hover, .nav-link-item.active {
            color: var(--primary-vigor-deep);
            background-color: rgba(0, 200, 83, 0.06);
        }

        .nav-link-item.active::after {
            content: '';
            position: absolute;
            bottom: 6px;
            left: 25%;
            width: 50%;
            height: 2.5px;
            background: var(--primary-vigor);
            border-radius: 2px;
        }

        /* Buttons */
        .btn-vigor {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            min-height: 46px;
            padding: 0.65rem 1.4rem;
            background: linear-gradient(135deg, #00C853 0%, #059669 100%);
            color: #FFFFFF;
            font-weight: 600;
            border-radius: var(--radius-btn);
            box-shadow: 0 6px 16px rgba(0, 200, 83, 0.26);
            transition: var(--transition-base);
            border: none;
            cursor: pointer;
        }

        .btn-vigor:hover {
            transform: translateY(-2px);
            box-shadow: 0 10px 24px rgba(0, 200, 83, 0.36);
            filter: brightness(1.04);
        }

        .btn-vigor:focus-visible {
            outline: 3px solid rgba(0, 200, 83, 0.4);
            outline-offset: 2px;
        }

        .btn-kinetic {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            min-height: 46px;
            padding: 0.65rem 1.4rem;
            background: linear-gradient(135deg, #FF6D00 0%, #F97316 100%);
            color: #FFFFFF;
            font-weight: 600;
            border-radius: var(--radius-btn);
            box-shadow: 0 6px 16px rgba(255, 109, 0, 0.25);
            transition: var(--transition-base);
            border: none;
            cursor: pointer;
        }

        .btn-kinetic:hover {
            transform: translateY(-2px);
            box-shadow: 0 12px 24px rgba(255, 109, 0, 0.38);
        }

        .btn-outline-dark {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            min-height: 46px;
            padding: 0.65rem 1.4rem;
            background: rgba(255, 255, 255, 0.06);
            color: #F8FAFC;
            border: 1px solid rgba(255, 255, 255, 0.22);
            font-weight: 600;
            border-radius: var(--radius-btn);
            transition: var(--transition-base);
            cursor: pointer;
        }

        .btn-outline-dark:hover {
            background: rgba(0, 200, 83, 0.14);
            border-color: #00C853;
            color: #FFFFFF;
        }

        /* Section spacing & surfaces */
        .section-light {
            padding: 5.5rem 0;
            background-color: var(--bg-canvas);
            border-bottom: 1px solid var(--border-subtle);
        }

        .section-white {
            padding: 5.5rem 0;
            background-color: var(--bg-surface);
            border-bottom: 1px solid var(--border-subtle);
        }

        .section-dark {
            padding: 5.5rem 0;
            background-color: var(--bg-dark);
            color: var(--text-on-dark);
            position: relative;
            overflow: hidden;
        }

        /* Cards & Interactive states */
        .vital-card {
            background-color: var(--bg-surface);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-card);
            box-shadow: var(--shadow-card);
            transition: var(--transition-base);
            position: relative;
            overflow: hidden;
        }

        .vital-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-card-hover);
            border-color: rgba(0, 200, 83, 0.35);
        }

        .dark-glass-card {
            background: rgba(22, 31, 36, 0.82);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: var(--radius-card);
            backdrop-filter: blur(10px);
            transition: var(--transition-base);
        }

        .dark-glass-card:hover {
            border-color: rgba(0, 200, 83, 0.45);
            box-shadow: 0 16px 32px rgba(0, 200, 83, 0.12);
        }

        /* Pulse dot animation */
        @keyframes pulse-ring {
            0% { transform: scale(0.85); opacity: 0.9; }
            70% { transform: scale(1.9); opacity: 0; }
            100% { transform: scale(1.9); opacity: 0; }
        }

        .pulse-indicator {
            position: relative;
            display: inline-block;
            width: 9px;
            height: 9px;
            border-radius: 50%;
            background-color: #00C853;
        }

        .pulse-indicator::before {
            content: '';
            position: absolute;
            inset: -3px;
            border-radius: 50%;
            background-color: #00C853;
            animation: pulse-ring 2s infinite;
        }

        /* Telemetry Matrix Grid in Hero */
        .hero-matrix-stage {
            background-color: #0F1416;
            background-image: linear-gradient(135deg, rgba(15, 20, 22, 0.94) 0%, rgba(15, 20, 22, 0.84) 60%, rgba(5, 150, 105, 0.25) 100%), url('/assets/images/d7414aa5b13d7db2.webp');
            background-size: cover;
            background-position: center;
            color: #FFFFFF;
            padding: 3.5rem 0 4.5rem;
            border-bottom: 1px solid rgba(0, 200, 83, 0.25);
        }

        .icon-matrix-cell {
            background: rgba(255, 255, 255, 0.04);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 14px;
            padding: 1.15rem;
            cursor: pointer;
            transition: var(--transition-base);
        }

        .icon-matrix-cell:hover, .icon-matrix-cell.active-cell {
            background: rgba(0, 200, 83, 0.14);
            border-color: #00C853;
            transform: translateY(-2px);
        }

        .data-num {
            font-family: "DIN Alternate", "JetBrains Mono", "Courier New", monospace;
            letter-spacing: -0.02em;
        }

        /* Progress Bar Animation */
        .metric-bar-bg {
            width: 100%;
            height: 10px;
            background: rgba(255, 255, 255, 0.08);
            border-radius: 999px;
            overflow: hidden;
        }

        .metric-bar-fill-vigor {
            height: 100%;
            background: linear-gradient(90deg, #00C853, #34D399);
            border-radius: 999px;
        }

        .metric-bar-fill-warn {
            height: 100%;
            background: linear-gradient(90deg, #EF4444, #F97316);
            border-radius: 999px;
        }

        /* Accordion */
        .faq-item-box {
            border: 1px solid var(--border-subtle);
            border-radius: 14px;
            background: #FFFFFF;
            transition: var(--transition-base);
            overflow: hidden;
        }

        .faq-item-box.open {
            border-color: #00C853;
            box-shadow: 0 10px 25px -5px rgba(0, 200, 83, 0.1);
        }

        /* Responsive adjustments */
        @media (max-width: 1024px) {
            .section-light, .section-white, .section-dark {
                padding: 4rem 0;
            }
            .hero-matrix-stage {
                padding: 2.5rem 0 3.5rem;
            }
        }

        @media (max-width: 768px) {
            .section-light, .section-white, .section-dark {
                padding: 3.25rem 0;
            }
            .top-utility-bar {
                font-size: 0.72rem;
                padding: 0.35rem 0;
            }
            h1 {
                font-size: 2rem !important;
                line-height: 1.22 !important;
            }
            h2 {
                font-size: 1.55rem !important;
                line-height: 1.3 !important;
            }
        }

        @media (max-width: 520px) {
            .container-custom {
                padding-left: 1rem;
                padding-right: 1rem;
            }
            .btn-vigor, .btn-kinetic, .btn-outline-dark {
                width: 100%;
            }
        }