:root {
            --bg-deep: #060b16;
            --bg-primary: #0b1120;
            --bg-secondary: #111b2e;
            --bg-card: rgba(255, 255, 255, 0.035);
            --bg-card-hover: rgba(255, 255, 255, 0.06);
            --border-glass: rgba(255, 255, 255, 0.07);
            --border-active: rgba(6, 182, 212, 0.3);
            --text-primary: #f0f4ff;
            --text-secondary: rgba(240, 244, 255, 0.7);
            --text-muted: rgba(240, 244, 255, 0.4);
            --accent-cyan: #06b6d4;
            --accent-teal: #34d399;
            --accent-indigo: #8b5cf6;
            --accent-blue: #3b82f6;
            --accent-amber: #f59e0b;
            --accent-gold: #fbbf24;
            --accent-rose: #f43f5e;
            --gradient-main: linear-gradient(135deg, #06b6d4, #34d399);
            --gradient-lets: linear-gradient(135deg, #f59e0b, #fbbf24, #f59e0b);
            --gradient-glow: linear-gradient(135deg, rgba(6, 182, 212, 0.2), rgba(52, 211, 153, 0.15));
            --gradient-glow-lets: linear-gradient(135deg, rgba(245, 158, 11, 0.2), rgba(251, 191, 36, 0.1));
            --shadow-glow: 0 0 80px rgba(6, 182, 212, 0.07), 0 0 160px rgba(52, 211, 153, 0.03);
            --shadow-glow-lets: 0 0 80px rgba(245, 158, 11, 0.07), 0 0 160px rgba(251, 191, 36, 0.04);
            --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', Roboto, sans-serif;
            --radius-xl: 32px;
            --radius-lg: 24px;
            --radius-md: 16px;
            --radius-sm: 10px;
            --radius-xs: 6px;
            --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
            --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            scroll-padding-top: 90px;
        }
        body {
            font-family: var(--font-family);
            background: var(--bg-deep);
            color: var(--text-primary);
            line-height: 1.6;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
        }
        ::-webkit-scrollbar {
            width: 5px;
        }
        ::-webkit-scrollbar-track {
            background: var(--bg-deep);
        }
        ::-webkit-scrollbar-thumb {
            background: var(--accent-cyan);
            border-radius: 10px;
        }
        canvas#particles {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: 0;
            pointer-events: none;
            opacity: 0.28;
        }
        .app {
            position: relative;
            z-index: 1;
        }
        .container {
            max-width: 1240px;
            margin: 0 auto;
            padding: 0 28px;
        }
        @media (max-width: 640px) {
            .container {
                padding: 0 16px;
            }
        }
        /* HEADER 统一首页风格 */
        header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 100;
            padding: 12px 0;
            background: rgba(6, 11, 22, 0.55);
            backdrop-filter: blur(24px);
            -webkit-backdrop-filter: blur(24px);
            border-bottom: 1px solid var(--border-glass);
            transition: all var(--transition-smooth);
        }
        header.scrolled {
            background: rgba(6, 11, 22, 0.94);
            box-shadow: 0 4px 50px rgba(0, 0, 0, 0.55);
            padding: 8px 0;
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 10px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            text-decoration: none;
            font-weight: 800;
            font-size: 20px;
            color: var(--text-primary);
            letter-spacing: -0.3px;
            flex-shrink: 0;
        }
        .logo-icon {
            width: 34px;
            height: 34px;
            border-radius: var(--radius-sm);
            background: var(--gradient-main);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 15px;
            font-weight: 900;
            color: #fff;
            box-shadow: 0 0 36px rgba(6, 182, 212, 0.22);
            transition: transform var(--transition-smooth);
        }
        .logo:hover .logo-icon {
            transform: scale(1.06) rotate(-5deg);
        }
        .logo span {
            background: var(--gradient-main);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        nav {
            display: flex;
            align-items: center;
            gap: 2px;
            flex-wrap: wrap;
        }
        nav a {
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 13.5px;
            font-weight: 500;
            padding: 7px 14px;
            border-radius: var(--radius-sm);
            transition: all var(--transition-fast);
            position: relative;
            white-space: nowrap;
        }
        nav a:hover {
            color: #fff;
            background: rgba(255, 255, 255, 0.05);
        }
        nav a.active {
            color: #fff;
            background: rgba(6, 182, 212, 0.13);
            box-shadow: 0 0 18px rgba(6, 182, 212, 0.04);
            font-weight: 600;
        }
        nav a.active::after {
            content: '';
            position: absolute;
            bottom: 3px;
            left: 50%;
            transform: translateX(-50%);
            width: 16px;
            height: 2px;
            border-radius: 2px;
            background: var(--gradient-main);
        }
        nav a.nav-letsvpn {
            color: var(--accent-gold);
            font-weight: 700;
            border: 1px solid rgba(245, 158, 11, 0.25);
            background: rgba(245, 158, 11, 0.06);
            animation: nav-pulse 3s ease-in-out infinite;
        }
        @keyframes nav-pulse {
            0%,100%{box-shadow:0 0 6px rgba(245,158,11,0.06);}
            50%{box-shadow:0 0 20px rgba(245,158,11,0.16);}
        }
        nav a.nav-letsvpn:hover {
            background: rgba(245, 158, 11, 0.14);
            border-color: rgba(245, 158, 11, 0.45);
            color: #fde68a;
        }
        .header-actions {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .btn-header {
            padding: 7px 18px;
            border-radius: var(--radius-sm);
            background: var(--gradient-main);
            color: #fff;
            font-size: 13px;
            font-weight: 600;
            text-decoration: none;
            transition: all var(--transition-smooth);
            box-shadow: 0 0 28px rgba(6, 182, 212, 0.14);
        }
        .btn-header:hover {
            transform: translateY(-2px);
            box-shadow: 0 0 48px rgba(6, 182, 212, 0.28);
        }
        .mobile-toggle {
            display: none;
            flex-direction: column;
            gap: 4px;
            background: none;
            border: none;
            cursor: pointer;
            padding: 6px;
        }
        .mobile-toggle span {
            display: block;
            width: 24px;
            height: 2px;
            background: var(--text-primary);
            border-radius: 2px;
            transition: all 0.3s;
        }
        .mobile-toggle.active span:nth-child(1){transform:rotate(45deg) translate(5px,5px);}
        .mobile-toggle.active span:nth-child(2){opacity:0;}
        .mobile-toggle.active span:nth-child(3){transform:rotate(-45deg) translate(5px,-5px);}
        @media (max-width:920px){
            .mobile-toggle{display:flex;}
            nav{display:none;width:100%;flex-direction:column;padding:12px 0 6px;gap:1px;order:10;}
            nav.open{display:flex;}
            nav a{padding:11px 16px;font-size:14px;text-align:center;}
            nav a.active::after{display:none;}
            .header-actions .btn-header{display:none;}
            .header-actions .btn-header.mobile-show{display:inline-flex;font-size:12px;padding:6px 14px;}
        }
        @media (min-width:921px){.header-actions .btn-header.mobile-show{display:none;}}
        /* 页面头部 */
        .page-hero {
            padding: 140px 0 50px;
            text-align: center;
            position: relative;
        }
        .page-hero::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 60%;
            height: 1px;
            background: linear-gradient(90deg, transparent, var(--accent-cyan), transparent);
            opacity: 0.1;
        }
        .page-hero .section-label {
            display: inline-block;
            font-size: 11px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 2.8px;
            color: var(--accent-cyan);
            background: rgba(6, 182, 212, 0.06);
            padding: 4px 16px;
            border-radius: 50px;
            border: 1px solid rgba(6, 182, 212, 0.06);
            margin-bottom: 14px;
        }
        .page-hero h1 {
            font-size: clamp(38px, 5.5vw, 58px);
            font-weight: 800;
            letter-spacing: -1.5px;
            margin-bottom: 10px;
        }
        .page-hero h1 .highlight {
            background: var(--gradient-main);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-hero .sub {
            font-size: clamp(15px, 1.2vw, 18px);
            color: var(--text-secondary);
            max-width: 620px;
            margin: 0 auto;
            line-height: 1.75;
        }
        /* 四步上手 */
        .quick-start {
            padding: 50px 0 70px;
        }
        .step-grid {
            display: grid;
            grid-template-columns: repeat(4,1fr);
            gap:24px;
            margin-top:30px;
        }
        @media (max-width:820px){.step-grid{grid-template-columns:1fr 1fr;}}
        @media (max-width:480px){.step-grid{grid-template-columns:1fr;}}
        .step-card {
            padding: 28px 22px;
            border-radius: var(--radius-lg);
            background: var(--bg-card);
            border:1px solid var(--border-glass);
            transition: all var(--transition-smooth);
            text-align: center;
            position: relative;
        }
        .step-card::before {
            content: '';
            position: absolute;
            inset:0;
            background: var(--gradient-glow);
            opacity:0;
            transition: opacity 0.5s;
            border-radius: var(--radius-lg);
        }
        .step-card:hover{transform:translateY(-5px);border-color:rgba(6,182,212,0.14);box-shadow:var(--shadow-glow);}
        .step-card:hover::before{opacity:1;}
        .step-card .num {
            font-size:48px;
            font-weight:800;
            background:var(--gradient-main);
            -webkit-background-clip:text;
            -webkit-text-fill-color:transparent;
            background-clip:text;
            line-height:1;
            position:relative;
            z-index:1;
            margin-bottom:6px;
        }
        .step-card .icon{font-size:32px;display:block;margin-bottom:8px;position:relative;z-index:1;}
        .step-card h3{font-size:18px;font-weight:600;margin-bottom:6px;position:relative;z-index:1;}
        .step-card p{font-size:14px;color:var(--text-secondary);line-height:1.6;position:relative;z-index:1;}
        .step-card .link{display:inline-block;margin-top:12px;font-size:13px;font-weight:500;color:var(--accent-cyan);text-decoration:none;position:relative;z-index:1;transition:all 0.3s;}
        .step-card .link:hover{color:var(--accent-teal);}

        /* 平台指南 */
        .platform-guide{padding:30px 0 80px;border-top:1px solid var(--border-glass);}
        .guide-tabs{display:flex;gap:8px;flex-wrap:wrap;margin:28px 0 32px;justify-content:center;}
        .guide-tabs .tab{padding:10px 28px;border-radius:50px;background:var(--bg-card);border:1px solid var(--border-glass);color:var(--text-secondary);font-size:14px;font-weight:500;cursor:pointer;transition:all 0.3s;text-decoration:none;}
        .guide-tabs .tab:hover{background:rgba(255,255,255,0.04);}
        .guide-tabs .tab.active{background:rgba(6,182,212,0.1);border-color:rgba(6,182,212,0.15);color:var(--accent-cyan);}
        .guide-panels{display:grid;grid-template-columns:1fr 1fr;gap:28px;}
        @media(max-width:820px){.guide-panels{grid-template-columns:1fr;}}
        .panel{padding:28px 26px;border-radius:var(--radius-lg);background:var(--bg-card);border:1px solid var(--border-glass);transition:all 0.4s;}
        .panel:hover{border-color:rgba(6,182,212,0.08);box-shadow:var(--shadow-glow);}
        .panel .head{display:flex;align-items:center;gap:14px;margin-bottom:12px;}
        .panel .head .icon{font-size:28px;}
        .panel .head h3{font-size:20px;font-weight:700;}
        .panel ul{list-style:none;}
        .panel ul li{padding:6px 0;font-size:14px;color:var(--text-secondary);display:flex;align-items:flex-start;gap:10px;}
        .panel ul li::before{content:'▹';color:var(--accent-teal);font-weight:700;}
        .panel .btn-guide{display:inline-block;margin-top:14px;padding:8px 22px;border-radius:var(--radius-sm);background:rgba(6,182,212,0.06);border:1px solid rgba(6,182,212,0.06);color:var(--accent-cyan);font-size:13px;font-weight:500;text-decoration:none;transition:all 0.3s;}
        .panel .btn-guide:hover{background:rgba(6,182,212,0.12);transform:translateX(4px);}

        /* 永远连上保障 */
        .always-on{padding:40px 0 80px;border-top:1px solid var(--border-glass);}
        .always-on-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:30px;}
        @media(max-width:820px){.always-on-grid{grid-template-columns:1fr;max-width:400px;margin-left:auto;margin-right:auto;}}
        .always-on-card{padding:26px 20px;border-radius:var(--radius-lg);background:var(--bg-card);border:1px solid var(--border-glass);text-align:center;transition:all var(--transition-smooth);}
        .always-on-card:hover{transform:translateY(-4px);border-color:rgba(6,182,212,0.12);box-shadow:var(--shadow-glow);}
        .always-on-card .ao-icon{font-size:36px;margin-bottom:10px;display:block;}
        .always-on-card h4{font-size:17px;font-weight:600;margin-bottom:6px;}
        .always-on-card p{font-size:13.5px;color:var(--text-secondary);line-height:1.6;}

        /* 安全加速解析 */
        .security-accel{padding:30px 0 70px;border-top:1px solid var(--border-glass);}
        .security-accel-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px;align-items:center;max-width:900px;margin:0 auto;}
        @media(max-width:768px){.security-accel-grid{grid-template-columns:1fr;text-align:center;}}
        .security-accel-visual{border-radius:var(--radius-xl);background:var(--bg-card);border:1px solid var(--border-glass);padding:26px;display:flex;flex-direction:column;gap:16px;}
        .security-accel-visual .metric{display:flex;justify-content:space-between;align-items:center;font-size:14px;color:var(--text-secondary);}
        .security-accel-visual .bar{height:8px;border-radius:10px;background:rgba(255,255,255,0.04);overflow:hidden;}
        .security-accel-visual .fill{height:100%;border-radius:10px;background:var(--gradient-main);width:0%;transition:width 1.5s ease;}
        .security-accel-text h3{font-size:26px;font-weight:700;margin-bottom:8px;}
        .security-accel-text h3 .highlight{background:var(--gradient-main);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;}
        .security-accel-text p{color:var(--text-secondary);font-size:15px;line-height:1.7;}

        /* 场景锦囊 */
        .scenarios-guide{padding:30px 0 80px;border-top:1px solid var(--border-glass);}
        .scenarios-guide-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:30px;}
        @media(max-width:900px){.scenarios-guide-grid{grid-template-columns:1fr 1fr;}}
        @media(max-width:500px){.scenarios-guide-grid{grid-template-columns:1fr;max-width:320px;margin-left:auto;margin-right:auto;}}
        .scenario-tip{padding:22px 16px;border-radius:var(--radius-lg);background:var(--bg-card);border:1px solid var(--border-glass);text-align:center;transition:all var(--transition-smooth);}
        .scenario-tip:hover{transform:translateY(-3px);border-color:rgba(6,182,212,0.1);box-shadow:var(--shadow-glow);}
        .scenario-tip .st-icon{font-size:30px;margin-bottom:8px;}
        .scenario-tip h4{font-size:15px;font-weight:600;margin-bottom:4px;}
        .scenario-tip p{font-size:12.5px;color:var(--text-muted);}

        /* FAQ预览（优化后降低重复） */
        .faq-preview{padding:40px 0 80px;border-top:1px solid var(--border-glass);}
        .faq-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:30px;}
        @media(max-width:820px){.faq-grid{grid-template-columns:1fr;max-width:480px;margin-left:auto;margin-right:auto;}}
        .faq-item{padding:22px 24px;border-radius:var(--radius-md);background:var(--bg-card);border:1px solid var(--border-glass);transition:all 0.3s;}
        .faq-item:hover{border-color:rgba(6,182,212,0.08);}
        .faq-item .q{font-weight:600;font-size:15px;margin-bottom:4px;display:flex;align-items:center;gap:8px;}
        .faq-item .q .mark{color:var(--accent-cyan);font-size:18px;}
        .faq-item .a{font-size:14px;color:var(--text-secondary);line-height:1.6;}
        .faq-item .more{display:inline-block;margin-top:10px;font-size:13px;color:var(--accent-cyan);text-decoration:none;font-weight:500;}
        .faq-item .more:hover{color:var(--accent-teal);}

        /* 信任与下载条 */
        .trust{padding:30px 0 60px;border-top:1px solid var(--border-glass);}
        .trust-wrap{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:24px;padding:26px 34px;border-radius:var(--radius-xl);background:var(--bg-card);border:1px solid var(--border-glass);}
        .trust-wrap:hover{border-color:rgba(6,182,212,0.07);box-shadow:var(--shadow-glow);}
        .trust-left{display:flex;align-items:center;gap:16px;}
        .trust-left .badge-icon{width:48px;height:48px;border-radius:var(--radius-sm);background:var(--gradient-main);display:flex;align-items:center;justify-content:center;font-size:19px;color:#fff;}
        .trust-right{display:flex;gap:9px;flex-wrap:wrap;}
        .trust-right .tag{padding:5px 14px;border-radius:50px;font-size:11.5px;background:rgba(255,255,255,0.025);border:1px solid var(--border-glass);color:var(--text-secondary);}
        .trust-right .tag.verified{background:rgba(6,182,212,0.04);border-color:rgba(6,182,212,0.07);color:var(--accent-cyan);}

        .cta-strip{padding:20px 0 40px;}
        .cta-strip-inner{padding:26px 32px;border-radius:var(--radius-xl);background:linear-gradient(135deg,rgba(6,182,212,0.06),rgba(52,211,153,0.04));border:1px solid rgba(6,182,212,0.08);text-align:center;}
        .cta-strip-inner h3{font-size:22px;font-weight:700;}
        .cta-strip-inner .btn-primary{display:inline-flex;margin-top:12px;padding:12px 36px;border-radius:var(--radius-md);background:var(--gradient-main);color:#fff;font-weight:600;text-decoration:none;box-shadow:0 0 30px rgba(6,182,212,0.15);transition:all 0.3s;}
        .cta-strip-inner .btn-primary:hover{transform:translateY(-2px);box-shadow:0 0 50px rgba(6,182,212,0.3);}

        footer{padding:32px 0 24px;border-top:1px solid var(--border-glass);}
        .footer-inner{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:16px;font-size:12.5px;}
        .footer-inner .copy{color:var(--text-muted);}
        .footer-links{display:flex;gap:20px;flex-wrap:wrap;}
        .footer-links a{color:var(--text-muted);text-decoration:none;transition:color var(--transition-fast);}
        .footer-links a:hover{color:var(--text-primary);}

        .scroll-top{position:fixed;bottom:28px;right:28px;width:44px;height:44px;border-radius:50%;background:var(--bg-card);border:1px solid var(--border-glass);color:var(--text-secondary);font-size:17px;cursor:pointer;backdrop-filter:blur(10px);opacity:0;transform:translateY(20px);pointer-events:none;z-index:50;display:flex;align-items:center;justify-content:center;transition:all var(--transition-smooth);}
        .scroll-top.visible{opacity:1;transform:translateY(0);pointer-events:auto;}
        .scroll-top:hover{background:rgba(6,182,212,0.07);border-color:rgba(6,182,212,0.14);color:var(--accent-cyan);}
        .sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);}