body {
            background-color: #0f172a;
            background-image: 
                radial-gradient(at 0% 0%, hsla(253,16%,7%,1) 0, transparent 50%), 
                radial-gradient(at 50% 0%, hsla(225,39%,30%,0.2) 0, transparent 50%), 
                radial-gradient(at 100% 0%, hsla(339,49%,30%,0.2) 0, transparent 50%);
            color: #f8fafc;
            min-height: 100vh;
        }
        .glass-card {
            background: rgba(30, 41, 59, 0.7);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 1.25rem;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        .glass-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
            border: 1px solid rgba(255, 255, 255, 0.2);
        }
        .text-gradient {
            background-clip: text;
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .gradient-main {
            background-image: linear-gradient(to right, #38bdf8, #818cf8, #c084fc);
        }
        .progress-bar-animated {
            animation: fillBar 1.5s ease-out forwards;
        }
        @keyframes fillBar {
            from { width: 0; }
        }
        
        .reveal {
            opacity: 0;
            transform: translateY(40px);
            transition: all 0.8s ease-out;
        }
        .reveal.active {
            opacity: 1;
            transform: translateY(0);
        }
        /* Các class delay để tạo hiệu ứng xuất hiện lần lượt cho từng thẻ trong grid */
        .delay-100 { transition-delay: 0.1s; }
        .delay-200 { transition-delay: 0.2s; }
        .delay-300 { transition-delay: 0.3s; }