:root {
            --navy-900: #0a1428;
            --navy-800: #0f1d35;
            --navy-700: #16294a;
            --navy-600: #1d3761;
            --navy-500: #274a7a;
            --orange-500: #ff6b35;
            --orange-400: #ff8c42;
            --orange-300: #ffab6e;
            --cyan-500: #00b4d8;
            --cyan-400: #2ec4d6;
            --bg-light: #f7f9fc;
            --bg-white: #ffffff;
            --text-dark: #0f1626;
            --text-mid: #3a4a5f;
            --text-light: #6b7d93;
            --border-light: #e3e8f0;
            --shadow-sm: 0 2px 12px rgba(10, 20, 40, 0.06);
            --shadow-md: 0 8px 30px rgba(10, 20, 40, 0.1);
            --shadow-lg: 0 20px 60px rgba(10, 20, 40, 0.15);
            --radius-sm: 10px;
            --radius-md: 18px;
            --radius-lg: 26px;
            --radius-xl: 36px;
            --font-sans: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
            --transition: 0.28s cubic-bezier(0.25, 0.46, 0.45, 0.94);
        }
        *,
        *::before,
        *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
        body { font-family: var(--font-sans); background: var(--bg-white); color: var(--text-dark); line-height: 1.65; font-size: 16px; overflow-x: hidden; }
        a { color: inherit; text-decoration: none; transition: color var(--transition); }
        a:hover { color: var(--orange-500); }
        img { max-width: 100%; display: block; }
        ul, ol { list-style: none; }
        button { font-family: inherit; cursor: pointer; border: none; background: none; }
        .wrap { max-width: 1180px; margin: 0 auto; padding: 0 28px; }

        /* 顶部信息栏 */
        .topbar { background: var(--navy-900); color: #b8c7dd; font-size: 13.5px; padding: 9px 0; letter-spacing: 0.03em; border-bottom: 1px solid rgba(255, 107, 53, 0.25); }
        .topbar .wrap { display: flex; align-items: center; flex-wrap: wrap; gap: 6px 12px; }
        .topbar .tb-dot { color: var(--orange-400); font-weight: 700; margin-right: 4px; }
        .tb-sep { color: var(--orange-500); opacity: 0.6; font-size: 10px; }
        .topbar a { color: var(--orange-300); font-weight: 600; border-bottom: 1px dashed rgba(255, 171, 110, 0.4); }
        .topbar a:hover { color: #fff; border-bottom-color: #fff; }

        /* 导航栏 */
        .masthead { background: var(--bg-white); border-bottom: 1px solid var(--border-light); position: sticky; top: 0; z-index: 100; box-shadow: 0 1px 8px rgba(10, 20, 40, 0.04); }
        .masthead .wrap { display: flex; align-items: center; gap: 18px; height: 72px; }
        .wordmark { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
        .wm-mark { width: 42px; height: 42px; border-radius: 12px; background: linear-gradient(135deg, var(--navy-700), var(--navy-500)); display: flex; align-items: center; justify-content: center; color: #fff; font-weight: 800; font-size: 20px; box-shadow: 0 3px 12px rgba(10, 20, 40, 0.2); }
        .wm-text { display: flex; flex-direction: column; line-height: 1.15; }
        .wm-name { font-weight: 800; font-size: 22px; color: var(--navy-900); letter-spacing: -0.02em; }
        .wm-sub { font-size: 11px; color: var(--orange-500); font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; }
        .nav-wrap { display: flex; align-items: center; gap: 2px; margin-left: auto; flex-wrap: wrap; }
        .nav-wrap>a, .dd>button { display: inline-flex; align-items: center; gap: 4px; padding: 10px 14px; font-size: 15px; font-weight: 600; color: var(--text-mid); border-radius: 8px; transition: all var(--transition); white-space: nowrap; }
        .nav-wrap>a:hover, .dd>button:hover { color: var(--orange-500); background: #fff4ef; }
        .nav-wrap>a.on { color: var(--orange-500); background: #fff4ef; box-shadow: inset 0 -2px 0 var(--orange-500); }
        .dd { position: relative; }
        .dd-menu { position: absolute; top: calc(100% + 6px); left: 0; background: #fff; border-radius: 14px; box-shadow: var(--shadow-md); padding: 8px 0; min-width: 190px; opacity: 0; visibility: hidden; transform: translateY(8px); transition: all var(--transition); border: 1px solid var(--border-light); z-index: 50; }
        .dd:hover .dd-menu, .dd:focus-within .dd-menu { opacity: 1; visibility: visible; transform: translateY(0); }
        .dd-menu a { display: block; padding: 9px 18px; font-size: 14px; font-weight: 500; color: var(--text-mid); border-radius: 6px; transition: all 0.2s; }
        .dd-menu a:hover { background: #fff4ef; color: var(--orange-500); padding-left: 22px; }
        .nav-cta { background: linear-gradient(135deg, var(--orange-500), var(--orange-400)); color: #fff; padding: 10px 20px; border-radius: 30px; font-weight: 700; font-size: 14px; box-shadow: 0 4px 16px rgba(255, 107, 53, 0.35); transition: all var(--transition); white-space: nowrap; }
        .nav-cta:hover { transform: translateY(-1px); box-shadow: 0 6px 22px rgba(255, 107, 53, 0.45); color: #fff; }
        .nav-toggle-input { display: none; }
        .nav-toggle-label { display: none; font-size: 26px; color: var(--navy-900); cursor: pointer; padding: 6px 10px; border-radius: 8px; user-select: none; }
        @media (max-width: 860px) {
            .nav-wrap { position: fixed; top: 72px; right: 0; width: 300px; max-width: 85vw; height: calc(100vh - 72px); background: #fff; flex-direction: column; align-items: stretch; gap: 0; padding: 16px 20px 40px; box-shadow: -8px 0 40px rgba(10,20,40,0.12); transform: translateX(110%); transition: transform var(--transition); overflow-y: auto; border-left: 1px solid var(--border-light); }
            .nav-toggle-label { display: block; margin-left: auto; }
            .nav-toggle-input:checked~.nav-wrap { transform: translateX(0); }
            .nav-wrap>a, .dd>button { padding: 13px 16px; font-size: 16px; width: 100%; border-radius: 10px; }
            .dd-menu { position: static; opacity: 1; visibility: visible; transform: none; box-shadow: none; border: none; padding: 0 0 8px 20px; min-width: auto; }
            .dd-menu a { padding: 8px 14px; font-size: 14px; }
            .nav-cta { margin-top: 12px; text-align: center; justify-content: center; border-radius: 12px; }
            .masthead .wrap { height: 64px; }
        }
        /* 跑马灯 */
        .marquee { background: linear-gradient(90deg, var(--navy-900), var(--navy-700), var(--navy-900)); overflow: hidden; padding: 10px 0; border-bottom: 2px solid var(--orange-500); }
        .marquee-inner { display: flex; align-items: center; gap: 28px; white-space: nowrap; animation: marquee-scroll 28s linear infinite; width: max-content; color: #cdd9ea; font-size: 14px; font-weight: 500; letter-spacing: 0.05em; }
        .marquee-inner i { color: var(--orange-400); font-style: normal; font-size: 10px; }
        @keyframes marquee-scroll { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }

        /* Hero Windows 专属 */
        .hero-win {
            background: linear-gradient(155deg, #0a1428 0%, #0f1d35 30%, #1d3761 70%, #16294a 100%);
            position: relative;
            overflow: hidden;
            padding: 80px 0 90px;
            color: #fff;
        }
        .hero-win::before {
            content: '';
            position: absolute;
            inset: 0;
            background:
                radial-gradient(ellipse at 30% 20%, rgba(255, 107, 53, 0.18) 0%, transparent 50%),
                radial-gradient(ellipse at 70% 70%, rgba(0, 180, 216, 0.15) 0%, transparent 50%);
            pointer-events: none;
        }
        .hero-win .wrap {
            position: relative;
            z-index: 2;
            display: grid;
            grid-template-columns: 1.1fr 0.9fr;
            gap: 50px;
            align-items: center;
        }
        .win-pill {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: rgba(0, 180, 216, 0.12);
            border: 1px solid rgba(0, 180, 216, 0.35);
            padding: 7px 16px;
            border-radius: 30px;
            font-size: 13px;
            font-weight: 600;
            color: #7dd8e8;
            margin-bottom: 22px;
            letter-spacing: 0.04em;
        }
        .win-pill .win-flag {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--cyan-400);
            animation: ping-ring 1.8s ease-out infinite;
        }
        @keyframes ping-ring { 0% { box-shadow: 0 0 0 0 rgba(0,180,216,0.5); } 100% { box-shadow: 0 0 0 12px rgba(0,180,216,0); } }
        .hero-win h1 {
            font-size: clamp(2rem, 4vw, 3.2rem);
            font-weight: 800;
            line-height: 1.2;
            letter-spacing: -0.03em;
            margin-bottom: 18px;
            color: #fff;
        }
        .hero-win h1 .win-hl {
            background: linear-gradient(135deg, var(--orange-400), var(--cyan-400));
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
        }
        .win-sub {
            font-size: 16.5px;
            color: #b8c7dd;
            max-width: 520px;
            line-height: 1.75;
            margin-bottom: 32px;
        }
        .win-sub strong { color: #fff; font-weight: 700; }
        .win-hero-cta {
            display: flex;
            gap: 14px;
            flex-wrap: wrap;
            margin-bottom: 28px;
        }
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 14px 28px;
            border-radius: 40px;
            font-weight: 700;
            font-size: 15.5px;
            transition: all var(--transition);
            letter-spacing: 0.02em;
        }
        .btn-primary { background: linear-gradient(135deg, var(--orange-500), var(--orange-400)); color: #fff; box-shadow: 0 6px 24px rgba(255,107,53,0.4); }
        .btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 32px rgba(255,107,53,0.5); color: #fff; }
        .btn-ghost { background: rgba(255,255,255,0.08); border: 1.5px solid rgba(255,255,255,0.3); color: #fff; backdrop-filter: blur(6px); }
        .btn-ghost:hover { background: rgba(255,255,255,0.16); border-color: rgba(255,255,255,0.5); color: #fff; }
        .btn-outline { background: transparent; border: 2px solid var(--orange-500); color: var(--orange-500); font-weight: 600; }
        .btn-outline:hover { background: var(--orange-500); color: #fff; }
        .win-trust {
            display: flex;
            gap: 20px;
            flex-wrap: wrap;
            font-size: 13px;
            color: #9aafc8;
            font-weight: 500;
        }
        .win-trust span { display: flex; align-items: center; gap: 6px; }
        .win-trust span::before { content: '✓'; color: var(--cyan-400); font-weight: 800; font-size: 14px; }

        .win-visual {
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
        }
        .win-visual svg {
            width: 100%;
            max-width: 480px;
            height: auto;
            filter: drop-shadow(0 20px 60px rgba(0, 0, 0, 0.45));
        }
        @media (max-width: 900px) {
            .hero-win .wrap { grid-template-columns: 1fr; gap: 40px; text-align: center; }
            .win-sub { margin-left: auto; margin-right: auto; }
            .win-hero-cta { justify-content: center; }
            .win-trust { justify-content: center; }
            .win-visual { order: -1; }
            .hero-win { padding: 50px 0 60px; }
        }

        /* 版本信息条 */
        .version-strip { background: var(--bg-white); border-bottom: 1px solid var(--border-light); padding: 18px 0; }
        .version-strip .wrap { display: flex; align-items: center; flex-wrap: wrap; gap: 12px 28px; justify-content: center; text-align: center; }
        .v-item { display: flex; align-items: center; gap: 8px; font-size: 13.5px; color: var(--text-mid); font-weight: 500; }
        .v-item .v-ic { color: var(--orange-500); font-size: 18px; }
        .v-item strong { color: var(--navy-900); font-weight: 700; }

        /* 通用 section */
        .section { padding: 72px 0; }
        .section.alt { background: var(--bg-light); }
        .sec-head { text-align: center; margin-bottom: 46px; }
        .sec-head.left { text-align: left; }
        .sec-head .kicker { display: inline-block; font-size: 12.5px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase; color: var(--cyan-500); margin-bottom: 8px; background: #eef6fe; padding: 5px 14px; border-radius: 20px; }
        .sec-head h2 { font-size: clamp(1.6rem, 3vw, 2.4rem); font-weight: 800; color: var(--navy-900); letter-spacing: -0.02em; margin-top: 6px; }
        .sec-head p { color: var(--text-light); font-size: 16px; max-width: 580px; margin: 10px auto 0; }
        .sec-head.left p { margin-left: 0; }

        /* Windows 特色功能网格 */
        .win-features-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 22px;
        }
        .win-feature-card {
            background: #fff;
            border-radius: var(--radius-md);
            padding: 28px 20px;
            text-align: center;
            border: 1px solid var(--border-light);
            transition: all var(--transition);
            position: relative;
            overflow: hidden;
        }
        .win-feature-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 3px;
            background: linear-gradient(90deg, var(--cyan-500), var(--orange-400));
            opacity: 0;
            transition: opacity var(--transition);
        }
        .win-feature-card:hover {
            border-color: var(--orange-300);
            box-shadow: var(--shadow-sm);
            transform: translateY(-2px);
        }
        .win-feature-card:hover::before { opacity: 1; }
        .win-feature-card .wf-icon { font-size: 36px; margin-bottom: 10px; }
        .win-feature-card h3 { font-size: 16px; font-weight: 700; color: var(--navy-900); margin-bottom: 6px; }
        .win-feature-card p { font-size: 13px; color: var(--text-light); line-height: 1.6; }
        @media (max-width: 900px) { .win-features-grid { grid-template-columns: repeat(2, 1fr); } }
        @media (max-width: 500px) { .win-features-grid { grid-template-columns: 1fr; } }

        /* 模拟客户端窗口版块 */
        .client-preview {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 50px;
            align-items: center;
        }
        .window-mockup {
            background: var(--navy-900);
            border-radius: var(--radius-lg);
            padding: 0;
            overflow: hidden;
            box-shadow: var(--shadow-lg);
            border: 1px solid rgba(255,255,255,0.1);
            position: relative;
        }
        .window-titlebar {
            background: rgba(255,255,255,0.05);
            padding: 12px 20px;
            display: flex;
            align-items: center;
            gap: 8px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .titlebar-dots {
            display: flex;
            gap: 6px;
            margin-right: 12px;
        }
        .titlebar-dots span {
            width: 12px;
            height: 12px;
            border-radius: 50%;
            background: #ff5f57;
        }
        .titlebar-dots span:nth-child(2) { background: #febc2e; }
        .titlebar-dots span:nth-child(3) { background: #28c840; }
        .titlebar-title {
            color: #a0b1c6;
            font-size: 12px;
            font-weight: 600;
            letter-spacing: 0.04em;
        }
        .window-body {
            padding: 30px 25px;
            color: #fff;
            position: relative;
            z-index: 1;
        }
        .window-status {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 20px;
            background: rgba(0,180,216,0.1);
            padding: 12px 16px;
            border-radius: 10px;
            border: 1px solid rgba(0,180,216,0.2);
        }
        .status-indicator {
            width: 10px;
            height: 10px;
            border-radius: 50%;
            background: var(--cyan-400);
            animation: pulse-dot 2s infinite;
        }
        @keyframes pulse-dot { 0%,100% { box-shadow: 0 0 0 0 rgba(0,180,216,0.4); } 50% { box-shadow: 0 0 0 8px rgba(0,180,216,0); } }
        .status-text { font-size: 14px; font-weight: 600; color: #fff; }
        .window-node-list {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .node-item {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 10px 14px;
            background: rgba(255,255,255,0.04);
            border-radius: 8px;
            font-size: 13px;
            color: #cdd9ea;
        }
        .node-item .node-name { font-weight: 600; color: #fff; }
        .node-item .node-latency { color: var(--cyan-400); font-weight: 700; }
        .client-preview .text-col h2 {
            font-size: clamp(1.5rem, 2.8vw, 2.2rem);
            font-weight: 800;
            color: var(--navy-900);
            margin-bottom: 14px;
        }
        .client-preview .text-col p {
            color: var(--text-light);
            font-size: 15.5px;
            margin-bottom: 18px;
            line-height: 1.7;
        }
        .client-preview .text-col ul {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .client-preview .text-col ul li {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 14px;
            color: var(--text-mid);
            font-weight: 500;
        }
        .client-preview .text-col ul li::before { content: '🖥️'; font-size: 13px; }
        @media (max-width: 800px) {
            .client-preview { grid-template-columns: 1fr; gap: 30px; }
        }

        /* 系统兼容性 */
        .compat-grid {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 18px;
        }
        .compat-item {
            background: #fff;
            border-radius: var(--radius-md);
            padding: 20px 28px;
            text-align: center;
            border: 1.5px solid var(--border-light);
            transition: all var(--transition);
            min-width: 150px;
        }
        .compat-item:hover {
            border-color: var(--cyan-400);
            box-shadow: var(--shadow-sm);
            transform: translateY(-2px);
        }
        .compat-item .compat-os {
            font-size: 16px;
            font-weight: 700;
            color: var(--navy-900);
        }
        .compat-item .compat-status {
            font-size: 12px;
            color: var(--cyan-500);
            font-weight: 600;
            margin-top: 4px;
        }

        /* 纯净承诺 */
        .pure-promise {
            background: linear-gradient(135deg, var(--navy-800), var(--navy-600));
            border-radius: var(--radius-lg);
            padding: 50px 40px;
            color: #fff;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .pure-promise::before { content: '🛡️'; position: absolute; right: 30px; top: 20px; font-size: 100px; opacity: 0.1; }
        .pure-promise h2 { font-size: clamp(1.6rem, 3vw, 2.3rem); font-weight: 800; letter-spacing: -0.02em; margin-bottom: 12px; }
        .pure-promise p { color: #b8c7dd; font-size: 16px; max-width: 600px; margin: 0 auto 20px; line-height: 1.7; }
        .pure-badges { display: flex; justify-content: center; gap: 20px; flex-wrap: wrap; margin-top: 20px; }
        .pure-badge {
            background: rgba(255,255,255,0.08);
            border: 1px solid rgba(255,255,255,0.15);
            padding: 10px 22px;
            border-radius: 30px;
            font-size: 14px;
            font-weight: 600;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .pure-badge span { font-size: 18px; }
        @media (max-width: 600px) {
            .pure-promise { padding: 36px 22px; }
            .pure-badges { flex-direction: column; align-items: center; }
        }

        /* FAQ */
        .faq-group details { background: #fff; border: 1px solid var(--border-light); border-radius: var(--radius-sm); margin-bottom: 10px; overflow: hidden; transition: all var(--transition); }
        .faq-group details:hover { border-color: #c9d4e3; }
        .faq-group summary { padding: 18px 22px; font-weight: 700; font-size: 15px; color: var(--navy-900); cursor: pointer; list-style: none; display: flex; align-items: center; justify-content: space-between; gap: 12px; user-select: none; }
        .faq-group summary::-webkit-details-marker { display: none; }
        .faq-group summary::after { content: '+'; font-size: 22px; color: var(--cyan-500); font-weight: 700; flex-shrink: 0; transition: transform 0.3s; }
        .faq-group details[open] summary::after { transform: rotate(45deg); }
        .faq-a { padding: 0 22px 20px; font-size: 14.5px; color: var(--text-mid); line-height: 1.7; }

        /* CTA */
        .cta-band { background: linear-gradient(135deg, var(--orange-500), var(--orange-400), var(--cyan-500)); border-radius: var(--radius-lg); padding: 50px 40px; text-align: center; color: #fff; position: relative; overflow: hidden; }
        .cta-band::before { content: ''; position: absolute; top: -60%; left: -50%; width: 200%; height: 200%; background: radial-gradient(circle at 50% 50%, rgba(255,255,255,0.12) 0%, transparent 60%); animation: cta-glow 5s ease-in-out infinite; }
        @keyframes cta-glow { 0%,100% { opacity: 0.3; } 50% { opacity: 0.6; } }
        .cta-band h2 { font-size: clamp(1.6rem, 3vw, 2.3rem); font-weight: 800; letter-spacing: -0.02em; position: relative; z-index: 1; }
        .cta-band p { font-size: 16px; opacity: 0.95; margin: 8px 0 26px; position: relative; z-index: 1; }
        .cta-band .btn { position: relative; z-index: 1; background: var(--navy-900); color: #fff; box-shadow: 0 8px 24px rgba(10,20,40,0.3); }
        .cta-band .btn:hover { background: var(--navy-800); transform: translateY(-2px); }

        /* Footer */
        .mastfoot { background: var(--navy-900); color: #a0b1c6; padding: 50px 0 24px; border-top: 3px solid var(--orange-500); }
        .mf-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 36px; }
        .mf-brand .wordmark { margin-bottom: 14px; }
        .mf-brand .wm-name { color: #fff; }
        .mf-brand .wm-sub { color: var(--orange-400); }
        .mf-brand p { font-size: 13.5px; color: #8a9bb5; max-width: 300px; line-height: 1.7; }
        .mf-col h4 { color: #fff; font-size: 15px; font-weight: 700; margin-bottom: 14px; letter-spacing: 0.04em; }
        .mf-col a { display: block; font-size: 13.5px; color: #8a9bb5; padding: 5px 0; transition: all 0.25s; }
        .mf-col a:hover { color: var(--orange-400); padding-left: 6px; }
        .foot-line { border-top: 1px solid rgba(255,255,255,0.08); padding-top: 18px; font-size: 12.5px; color: #6b7d93; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 8px; }
        @media (max-width: 800px) { .mf-grid { grid-template-columns: 1fr 1fr; gap: 28px; } }
        @media (max-width: 500px) { .mf-grid { grid-template-columns: 1fr; } }

        @media (max-width: 600px) {
            .section { padding: 48px 0; }
            .wrap { padding: 0 18px; }
            .hero-win h1 { font-size: 1.8rem; }
            .win-sub { font-size: 15px; }
            .btn { padding: 12px 20px; font-size: 14px; }
        }