:root {
            --bg-deep: #060d17;
            --bg-card: rgba(14,22,36,0.75);
            --bg-card-hover: rgba(22,32,50,0.9);
            --border-soft: #1e2d40;
            --border-glow: rgba(12,230,181,0.22);
            --text-primary: #edf2f9;
            --text-secondary: #8899b4;
            --accent-teal: #0ce6b5;
            --accent-amber: #f0a500;
            --accent-purple: #8b5cf6;
            --gradient-hero: linear-gradient(135deg, #0ce6b5 0%, #6dd5ed 50%, #8b5cf6 100%);
            --radius-lg: 20px;
            --radius-xl: 28px;
        }
        *{margin:0;padding:0;box-sizing:border-box;}
        body{
            font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;
            background:var(--bg-deep);color:var(--text-primary);line-height:1.55;
            -webkit-font-smoothing:antialiased;
        }
        .container{max-width:1240px;margin:0 auto;padding:0 28px;}
        a{text-decoration:none;color:inherit;transition:color 0.2s;}

       /* ==================== 导航栏 ==================== */
header {
    background: rgba(6, 13, 23, 0.94);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--border-glow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    padding: 14px 0;
}

.brand {
    display: flex;
    flex-direction: column;
}

.brand-name {
    font-size: 1.7rem;
    font-weight: 800;
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    letter-spacing: -0.5px;
    line-height: 1.2;
}

.brand-accent {
    color: var(--accent-teal);
    -webkit-text-fill-color: var(--accent-teal);
}

.brand-tagline {
    font-size: 0.68rem;
    color: var(--text-secondary);
    letter-spacing: 0.3px;
    margin-top: 1px;
}

.nav-menu {
    display: flex;
    gap: 1.8rem;
    align-items: center;
    flex-wrap: wrap;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: #b0c0d4;
    position: relative;
    padding: 4px 0;
    transition: color 0.25s;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-teal);
    transition: width 0.28s;
    box-shadow: var(--shadow-glow-teal);
}

.nav-link:hover,
.nav-link.active {
    color: var(--accent-teal);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

        /* Hero */
        .tun-hero{text-align:center;padding:50px 0 30px;}
        .tun-hero h1{font-size:2.8rem;font-weight:800;background:linear-gradient(to right,#f0f6ff,#8899b4);-webkit-background-clip:text;background-clip:text;color:transparent;margin-bottom:12px;}
        .tun-hero .hero-sub{color:var(--text-secondary);font-size:1.1rem;max-width:700px;margin:0 auto;}
        .chip{display:inline-block;background:rgba(12,230,181,0.1);border:1px solid rgba(12,230,181,0.3);border-radius:30px;padding:6px 18px;font-size:0.8rem;color:var(--accent-teal);margin-bottom:20px;}

        /* 卡片通用 */
        .card{background:var(--bg-card);backdrop-filter:blur(8px);border:1px solid var(--border-soft);border-radius:var(--radius-lg);padding:30px 28px;transition:all 0.3s;}
        .card:hover{border-color:var(--accent-teal);transform:translateY(-4px);box-shadow:0 12px 30px rgba(0,0,0,0.5);}

        /* TUN 对比系统代理 */
        .versus-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:24px;margin:40px 0;}
        .versus-col h3{font-size:1.5rem;margin-bottom:16px;color:#f0f6ff;}
        .versus-list{list-style:none;font-size:0.95rem;}
        .versus-list li{padding:10px 0;display:flex;align-items:center;gap:8px;color:var(--text-secondary);border-bottom:1px solid rgba(255,255,255,0.05);}
        .versus-list li::before{content:"▹";color:var(--accent-teal);font-weight:bold;}

        /* 分流规则详解 */
        .rule-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:20px;margin:30px 0;}
        .rule-card{text-align:left;}
        .rule-card .rule-type{font-size:1.2rem;font-weight:700;color:var(--accent-teal);margin-bottom:8px;}
        .rule-card p{color:var(--text-secondary);font-size:0.9rem;line-height:1.6;}

        /* 高级玩法 */
        .advanced-row{display:flex;flex-wrap:wrap;gap:24px;margin:30px 0;}
        .advanced-card{flex:1 1 280px;display:flex;flex-direction:column;align-items:flex-start;}
        .advanced-card .icon{font-size:2.5rem;margin-bottom:12px;}
        .advanced-card h4{font-size:1.3rem;color:#f0f6ff;margin-bottom:8px;}
        .advanced-card p{color:var(--text-secondary);font-size:0.9rem;line-height:1.6;}

        /* 一键开启步骤 */
        .steps-mini{display:flex;flex-wrap:wrap;gap:20px;margin:30px 0;justify-content:center;}
        .step-mini{flex:0 0 180px;text-align:center;background:var(--bg-card);border-radius:16px;padding:24px 16px;border:1px solid var(--border-soft);}
        .step-mini .step-num{font-size:2rem;font-weight:800;background:var(--gradient-hero);-webkit-background-clip:text;background-clip:text;color:transparent;}
        .step-mini h5{color:#fff;margin:10px 0 6px;}

        /* 常见问题 */
        .faq-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:20px;margin:30px 0;}
        .faq-card h4{font-size:1.05rem;color:#f0f6ff;margin-bottom:10px;}
        .faq-card p{font-size:0.9rem;color:var(--text-secondary);}

        /* CTA */
        .cta-banner{position:relative;background:linear-gradient(135deg,#0a1620,#110d28);border-radius:var(--radius-xl);margin:50px 0 36px;overflow:hidden;padding:56px 0;}
        .cta-content{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:26px;position:relative;z-index:2;padding:0 32px;}
        .cta-text h2{font-size:1.9rem;color:#fff;margin-bottom:10px;}
        .cta-text p{color:#c0d0e0;max-width:500px;}
        .btn-glow{background:var(--gradient-hero);border:none;padding:14px 36px;border-radius:50px;font-weight:700;color:#061018;box-shadow:0 8px 22px rgba(12,230,181,0.3);display:inline-block;transition:all 0.3s;}
        .btn-glow:hover{transform:translateY(-2px);box-shadow:0 14px 30px rgba(12,230,181,0.5);}
        .btn-ghost{background:transparent;border:1px solid rgba(255,255,255,0.3);padding:14px 36px;border-radius:50px;color:#fff;font-weight:600;transition:all 0.3s;}
        .btn-ghost:hover{background:rgba(255,255,255,0.08);}
        .cta-dot{position:absolute;border-radius:50%;opacity:0.15;filter:blur(35px);}
        .cta-dot-1{width:180px;height:180px;top:-40px;right:-30px;background:var(--accent-teal);}
        .cta-dot-2{width:140px;height:140px;bottom:-25px;left:8%;background:var(--accent-amber);}
        .cta-dot-3{width:90px;height:90px;top:45%;left:58%;background:var(--accent-purple);}

        /* 页脚 */
        footer{background:#030a12;border-top:1px solid #1a2a3a;padding:50px 0 24px;}
        .footer-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:36px;}
        .footer-col h4{color:#f1f5f9;margin-bottom:16px;}
        .footer-col a{display:block;color:#8899b4;font-size:0.85rem;margin-bottom:7px;}
        .footer-col a:hover{color:var(--accent-teal);}
        .footer-bottom{text-align:center;padding-top:36px;color:#4a5568;font-size:0.75rem;border-top:1px solid #1a2a3a;margin-top:32px;}
        .footer-brand{font-size:1.3rem;font-weight:800;background:var(--gradient-hero);-webkit-background-clip:text;background-clip:text;color:transparent;margin-bottom:6px;}

        @media(max-width:768px){
            .container{padding:0 18px;}
            .nav-menu{display:none;flex-direction:column;width:100%;background:rgba(6,13,23,0.98);margin-top:14px;padding:14px 0;gap:10px;border-radius:14px;}
            .nav-menu--open{display:flex;}
            .menu-toggle{display:flex;}
            .tun-hero h1{font-size:2rem;}
            .cta-content{flex-direction:column;text-align:center;}
            .footer-grid{grid-template-columns:1fr 1fr;}
        }