:root {
    --neon-red: #ff1a1a;
    --neon-cyan: #00ffff;
    --neon-yellow: #ffff33;
    --neon-purple: #cc00ff;
    --dark-bg: rgba(10, 10, 25, 0.92);
    --glow: 0 0 12px;
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    background: linear-gradient(145deg, #0a0a1f, #1f1f3d);
    font-family: 'Roboto Mono', monospace;
    color: #fff;
    overflow-x: hidden;
    overflow-y: auto;
    padding: 20px 0;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('IMG/bg.png') repeat-x center;
    animation: bgMove 10s linear infinite;
    opacity: 0.12;
    z-index: -1;
    filter: blur(3px);
}

@keyframes bgMove {
    0% { background-position: 0 0; }
    100% { background-position: -1920px 0; }
}

.content {
    width: 90%;
    max-width: 1000px;
    margin: 0 auto;
    background: var(--dark-bg);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--glow) var(--neon-purple), inset 0 0 10px var(--neon-cyan);
    backdrop-filter: blur(12px);
    border: 1px solid var(--neon-cyan);
    animation: fadeIn 1.2s ease-in-out;
}

@keyframes fadeIn {
    0% { opacity: 0; transform: translateY(20px); }
    100% { opacity: 1; transform: translateY(0); }
}

.neon-text {
    font-size: 36px;
    font-family: 'Orbitron', sans-serif;
    font-weight: 700;
    text-transform: uppercase;
    animation: neonGlow 1.5s infinite alternate;
    letter-spacing: 4px;
    text-align: center;
    margin-bottom: 20px;
}

@keyframes neonGlow {
    0% { color: var(--neon-red); text-shadow: var(--glow) var(--neon-red); }
    100% { color: var(--neon-yellow); text-shadow: var(--glow) var(--neon-yellow); }
}

.back-btn {
    display: inline-block;
    padding: 10px 20px;
    background: linear-gradient(45deg, var(--neon-red), var(--neon-purple));
    color: #fff;
    text-decoration: none;
    font-family: 'Orbitron', sans-serif;
    font-weight: 600;
    border-radius: 8px;
    box-shadow: var(--glow) var(--neon-red);
    transition: var(--transition);
    margin-bottom: 20px;
}

.back-btn:hover {
    background: linear-gradient(45deg, var(--neon-purple), var(--neon-yellow));
    box-shadow: var(--glow) var(--neon-yellow);
    transform: translateY(-3px);
}

.download-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 25px;
    padding: 20px 0;
}

.download-item {
    background: rgba(255, 255, 255, 0.05);
    padding: 20px;
    border-radius: 15px;
    box-shadow: var(--glow) var(--neon-cyan);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    overflow: hidden;
}

.download-item:hover {
    transform: scale(1.05);
    box-shadow: var(--glow) var(--neon-yellow);
}

.download-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.download-item:hover::before {
    left: 100%;
}

.download-item img {
    width: 100%;
    border-radius: 10px;
    filter: drop-shadow(var(--glow) var(--neon-cyan));
    transition: transform 0.3s ease;
}

.download-item:hover img {
    transform: scale(1.1);
}

.download-item h3 {
    font-size: 18px;
    font-family: 'Orbitron', sans-serif;
    color: var(--neon-cyan);
    margin: 15px 0 10px;
    text-transform: uppercase;
}

.download-item p {
    font-size: 14px;
    color: #e0e0e0;
    margin-bottom: 15px;
}

.download-btn, .desc-btn {
    display: inline-block;
    padding: 10px 15px;
    border-radius: 8px;
    text-decoration: none;
    font-family: 'Orbitron', sans-serif;
    font-weight: 600;
    color: #fff;
    transition: var(--transition);
    width: 100%;
    text-align: center;
    margin: 5px 0;
}

.download-btn {
    background: linear-gradient(45deg, var(--neon-cyan), var(--neon-purple));
    box-shadow: var(--glow) var(--neon-cyan);
}

.download-btn:hover {
    background: linear-gradient(45deg, var(--neon-purple), var(--neon-yellow));
    box-shadow: var(--glow) var(--neon-yellow);
    transform: translateY(-3px);
}

.desc-btn {
    background: linear-gradient(45deg, #28a745, var(--neon-cyan));
    box-shadow: var(--glow) #28a745;
    cursor: pointer;
    border: none;
}

.desc-btn:hover {
    background: linear-gradient(45deg, var(--neon-cyan), var(--neon-yellow));
    box-shadow: var(--glow) var(--neon-yellow);
    transform: translateY(-3px);
}

.description-popup {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.98); /* Nền tối hơn */
    color: #fff;
    padding: 30px;
    border-radius: 15px;
    width: 90%;
    max-width: 450px; /* Tăng chiều rộng */
    max-height: 80vh; /* Giới hạn chiều cao */
    overflow-y: auto; /* Cho phép cuộn */
    text-align: center;
    box-shadow: 
        0 0 20px var(--neon-cyan),
        0 0 40px var(--neon-purple),
        inset 0 0 15px var(--neon-red); /* Ánh sáng neon mạnh hơn */
    border: 2px solid var(--neon-cyan); /* Viền sáng */
    z-index: 9999;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    animation: popupGlow 0.5s ease-in-out forwards; /* Animation mượt */
    backdrop-filter: blur(10px); /* Hiệu ứng mờ nền */
}

@keyframes popupGlow {
    0% {
        opacity: 0;
        transform: translate(-50%, -55%) scale(0.95);
        box-shadow: 0 0 10px var(--neon-cyan);
    }
    50% {
        box-shadow: 0 0 30px var(--neon-purple);
    }
    100% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
        box-shadow: 
            0 0 20px var(--neon-cyan),
            0 0 40px var(--neon-purple);
    }
}

.description-popup p {
    font-family: 'Orbitron', sans-serif; /* Font cyberpunk */
    font-size: 18px; /* Tăng kích thước chữ */
    font-weight: 400;
    color: var(--neon-cyan); /* Màu nổi bật */
    text-shadow: 0 0 8px var(--neon-cyan); /* Ánh sáng neon */
    margin-bottom: 25px;
    line-height: 1.6; /* Khoảng cách dòng */
    white-space: pre-wrap; /* Cho phép xuống dòng */
    word-wrap: break-word; /* Đảm bảo từ dài không tràn */
    padding: 10px;
}

.close-btn {
    background: linear-gradient(45deg, var(--neon-red), var(--neon-purple)); /* Gradient */
    color: #fff;
    padding: 12px 25px;
    border: none;
    border-radius: 10px;
    font-family: 'Orbitron', sans-serif;
    font-weight: 700;
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 0 15px var(--neon-red);
    text-transform: uppercase; /* Chữ in hoa */
}

.close-btn:hover {
    background: linear-gradient(45deg, var(--neon-yellow), var(--neon-cyan));
    color: #000;
    box-shadow: 0 0 20px var(--neon-yellow);
    transform: translateY(-3px) scale(1.05); /* Phóng to nhẹ */
}