:root {
    /* Tông màu Xanh lá sẫm & Cam đặc trưng ngành in */
    --bg-dark: #001b0c;
    --bg-mid: #005120;
    --primary: #124726;
    --accent: #E65100;
    --accent-glow: #FF6D00;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    
    /* Hiệu ứng kính bóng bẩy (Glossy) */
    --glossy-bg: linear-gradient(145deg, rgba(255, 255, 255, 0.05) 0%, rgba(0, 0, 0, 0.4) 100%);
    --glossy-border-top: rgba(255, 255, 255, 0.15);
    --glossy-border-left: rgba(255, 255, 255, 0.05);
}

* { box-sizing: border-box; scroll-behavior: smooth; }

body {
    margin: 0; padding: 0;
    background-color: var(--bg-dark);
    background-image: 
        radial-gradient(circle at 0% 0%, var(--bg-mid) 0%, transparent 50%),
        radial-gradient(circle at 100% 100%, var(--primary) 0%, transparent 50%);
    color: var(--text-main);
    font-family: 'Montserrat', sans-serif;
    overflow-x: hidden;
}

/* --- ĐỊNH DẠNG GLOSSY CARD DÙNG CHUNG --- */
.glossy-card {
    background: var(--glossy-bg);
    border-top: 1px solid var(--glossy-border-top);
    border-left: 1px solid var(--glossy-border-left);
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    position: relative;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-top 0.3s ease;
}
.glossy-card::before {
    content: ''; position: absolute; top: 0; left: -100%; width: 50%; height: 100%;
    background: linear-gradient(to right, rgba(255,255,255,0) 0%, rgba(255,255,255,0.05) 50%, rgba(255,255,255,0) 100%);
    transform: skewX(-25deg); transition: 0.5s; pointer-events: none;
}
.glossy-card:hover::before { left: 150%; }
.glossy-card:hover { 
    transform: translateY(-5px); 
    box-shadow: 0 15px 40px rgba(230, 81, 0, 0.15); 
    border-top: 1px solid var(--accent-glow);
}

/* --- HỆ THỐNG MENU 3 CẤP CHUYÊN NGHIỆP --- */
nav {
    position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;
    display: flex; justify-content: space-between; align-items: center;
    padding: 0 5%; height: 80px;
    background: rgba(4, 18, 10, 0.9);
    backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--primary);
    box-shadow: 0 4px 30px rgba(0,0,0,0.5);
}
.logo { font-size: 24px; font-weight: 900; letter-spacing: 1px; color: #fff; }
.logo span { color: var(--accent-glow); }

/* Cấp 1 */
.menu-tree { display: flex; list-style: none; margin: 0; padding: 0; height: 100%; }
.menu-item-l1 { position: relative; height: 100%; display: flex; align-items: center; }
.menu-item-l1 > a {
    color: var(--text-main); text-decoration: none; font-size: 14px; font-weight: 700;
    text-transform: uppercase; letter-spacing: 1px; padding: 0 20px; height: 100%;
    display: flex; align-items: center; transition: 0.2s;
}
.menu-item-l1:hover > a { color: var(--accent-glow); }

/* Cấp 2 (Dropdown) */
.dropdown-l2 {
    position: absolute; top: 80px; left: 0; background: #061f10;
    min-width: 220px; list-style: none; padding: 10px 0; margin: 0;
    border: 1px solid var(--primary); border-top: 3px solid var(--accent);
    box-shadow: 0 10px 20px rgba(0,0,0,0.6);
    opacity: 0; visibility: hidden; transform: translateY(10px);
    transition: all 0.25s ease;
}
.menu-item-l1:hover .dropdown-l2 { opacity: 1; visibility: visible; transform: translateY(0); }
.menu-item-l2 { position: relative; }
.menu-item-l2 a {
    color: var(--text-main); text-decoration: none; font-size: 13px; font-weight: 600;
    padding: 12px 20px; display: flex; justify-content: space-between; align-items: center; transition: 0.2s;
}
.menu-item-l2:hover > a { background: var(--primary); color: var(--accent-glow); }

/* Cấp 3 (Flyout) */
.flyout-l3 {
    position: absolute; top: -10px; left: 100%; background: #092c17;
    min-width: 200px; list-style: none; padding: 10px 0; margin: 0;
    border: 1px solid var(--primary); box-shadow: 0 10px 20px rgba(0,0,0,0.6);
    opacity: 0; visibility: hidden; transform: translateX(10px);
    transition: all 0.25s ease;
}
.menu-item-l2:hover .flyout-l3 { opacity: 1; visibility: visible; transform: translateX(0); }
.menu-item-l3 a { padding: 10px 20px; font-size: 13px; font-weight: 500; }
.menu-item-l3 a:hover { background: var(--accent); color: #fff; }

/* Mũi tên chỉ có cấp con */
.has-children::after { content: ' ▾'; font-size: 10px; margin-left: 5px; color: var(--text-muted); }
.menu-item-l2.has-children::after { content: ' ▸'; position: absolute; right: 15px; top: 12px; }

/* --- FOOTER ĐỒNG BỘ --- */
footer { background: #020805; border-top: 2px solid var(--primary); padding: 70px 8% 30px; }
.footer-content { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 50px; margin-bottom: 50px; }
.footer-about h3 { font-size: 24px; font-weight: 900; margin: 0 0 20px; }
.footer-about h3 span { color: var(--accent-glow); }
.footer-about p { color: var(--text-muted); font-size: 15px; line-height: 1.8; margin: 0; max-width: 450px; }
.footer-links h4 { font-size: 16px; font-weight: 800; text-transform: uppercase; color: #fff; margin: 0 0 25px; letter-spacing: 1px;}
.footer-links ul { list-style: none; padding: 0; margin: 0; }
.footer-links li { margin-bottom: 15px; }
.footer-links a { color: var(--text-muted); text-decoration: none; font-size: 15px; font-weight: 500; transition: 0.2s; }
.footer-links a:hover { color: var(--accent-glow); }
.copyright { text-align: center; font-size: 13px; color: #4a5568; border-top: 1px solid rgba(255,255,255,0.05); padding-top: 30px; font-weight: 500;}