/* roulang page: index */
:root {
            --primary: #00B569;
            --secondary: #00F0FF;
            --dark: #0B131E;
            --light: #F8FAFC;
            --text-main: #0F172A;
            --text-body: #334155;
            --text-muted: #64748B;
            --radius: 8px;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
            --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.1);
        }

        * { box-sizing: border-box; margin: 0; padding: 0; }
        body { font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif; line-height: 1.75; color: var(--text-body); background: #fff; }
        
        .container { max-width: 1240px; margin: 0 auto; padding: 0 32px; }
        
        /* Header */
        .header { background: #fff; border-bottom: 1px solid #E2E8F0; position: sticky; top: 0; z-index: 100; }
        .top-bar { font-size: 12px; padding: 8px 0; background: var(--dark); color: #fff; display: flex; justify-content: space-between; }
        .nav-bar { display: flex; align-items: center; justify-content: space-between; padding: 16px 0; }
        .logo { font-size: 20px; font-weight: 800; color: var(--primary); text-decoration: none; }
        .nav-links a { margin-left: 24px; text-decoration: none; color: var(--text-main); font-weight: 500; font-size: 14px; }
        
        /* Hero */
        .hero { padding: 80px 0; background: #0B131E; color: #fff; text-align: center; }
        .hero h1 { font-size: 48px; margin-bottom: 24px; line-height: 1.2; }
        .hero p { font-size: 18px; color: #CBD5E1; max-width: 700px; margin: 0 auto 32px; }
        .btn { display: inline-block; padding: 12px 28px; border-radius: var(--radius); font-weight: 600; cursor: pointer; transition: 0.3s; text-decoration: none; }
        .btn-primary { background: var(--primary); color: #fff; }
        .btn-primary:hover { transform: translateY(-2px); box-shadow: 0 4px 14px rgba(0,181,105,0.3); }

        /* Sections */
        section { padding: 80px 0; }
        h2 { font-size: 36px; color: var(--text-main); margin-bottom: 48px; text-align: center; }
        .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
        .card { padding: 32px; border-radius: var(--radius); border: 1px solid #E2E8F0; background: #fff; transition: 0.3s; }
        .card:hover { border-color: var(--primary); box-shadow: var(--shadow-lg); }

        /* Footer */
        .footer { background: var(--dark); color: #94A3B8; padding: 60px 0 20px; text-align: center; }
        
        /* Mobile */
        @media (max-width: 768px) {
            .grid-3 { grid-template-columns: 1fr; }
            .hero h1 { font-size: 32px; }
            .nav-links { display: none; }
        }