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

:root {
  --gold: #f0a500;
  --gold-light: #ffd166;
  --dark: #0d0d1a;
  --dark2: #13131f;
  --dark3: #1a1a2e;
  --card: #16213e;
  --card2: #1e2a45;
  --text: #e0e0f0;
  --text-muted: #8888aa;
  --accent: #e94560;
  --green: #06d6a0;
  --radius: 14px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Be Vietnam Pro', sans-serif;
  background: var(--dark);
  color: var(--text);
  line-height: 1.6;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.accent { color: var(--gold); }

/* HEADER */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(13,13,26,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(240,165,0,0.15);
  padding: 14px 0;
  transition: all 0.3s;
}
.nav-container { max-width: 100%; margin: 0; padding: 0 24px; display: flex; align-items: center; gap: 12px; flex-wrap: nowrap; }
.logo { font-size: 1.5rem; font-weight: 800; display: flex; align-items: center; gap: 8px; color: #fff; text-decoration: none; white-space: nowrap; }
.logo i { color: var(--gold); }
.nav-links { display: flex; gap: 12px; margin-left: 0; flex-wrap: nowrap; }
.nav-links a { color: #000; text-decoration: none; font-weight: 500; transition: color 0.2s; white-space: nowrap; }
.nav-links a:hover { color: var(--dark); }
.btn-nav {
  background: var(--gold); color: #000; padding: 8px 20px;
  border-radius: 8px; font-weight: 700; text-decoration: none;
  transition: background 0.2s, transform 0.2s; white-space: nowrap;
}
.btn-nav:hover { background: var(--gold-light); transform: translateY(-1px); }
.btn-hotline { background: transparent; border: 2px solid var(--gold); color: var(--gold); }
.btn-hotline:hover { background: rgba(240,165,0,0.12); }

/* HERO */
.hero {
  width: 100%;
  padding-top: 70px;
  background: #07070f;
  line-height: 0;
}
.hero-img {
  width: 100%;
  height: auto;
  display: block;
}

/* hero-bg, hero-canvas, hero-content, hero-badge, hero-actions, hero-stats - removed */

/* SECTION */
.section { padding: 90px 0; }
.section-dark { background: var(--dark2); }
.section-why { background: var(--dark3); }
.section-header { text-align: center; margin-bottom: 60px; }
.section-tag {
  display: inline-flex; align-items: center; gap: 6px;
  background: rgba(240,165,0,0.1); border: 1px solid rgba(240,165,0,0.25);
  color: var(--gold); padding: 5px 14px; border-radius: 50px;
  font-size: 0.82rem; font-weight: 600; margin-bottom: 14px;
}
.section-header h2 { font-size: clamp(1.6rem, 3vw, 2.4rem); font-weight: 800; margin-bottom: 12px; }
.section-header p { color: var(--text-muted); max-width: 600px; margin: 0 auto; }

/* PRODUCT CARD */
.product-card {
  background: var(--card);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 40px;
  transition: border-color 0.3s, box-shadow 0.3s;
}
.product-card:hover {
  border-color: rgba(240,165,0,0.3);
  box-shadow: 0 8px 40px rgba(240,165,0,0.08);
}
.product-header {
  display: flex; align-items: flex-start; gap: 20px;
  margin-bottom: 28px; flex-wrap: wrap;
}
.product-icon {
  width: 52px; height: 52px; border-radius: 12px;
  background: rgba(240,165,0,0.12); display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem; color: var(--gold); flex-shrink: 0;
}
.product-header h3 { font-size: 1.25rem; font-weight: 700; margin-bottom: 4px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.product-header p { color: var(--text-muted); font-size: 0.9rem; }
.product-price { margin-left: auto; font-size: 1.1rem; font-weight: 700; color: var(--gold); white-space: nowrap; }

/* BADGES */
.badge {
  font-size: 0.7rem; font-weight: 700; padding: 3px 10px;
  border-radius: 50px; text-transform: uppercase; letter-spacing: 0.5px;
}
.badge-hot { background: rgba(233,69,96,0.2); color: #e94560; border: 1px solid rgba(233,69,96,0.3); }
.badge-new { background: rgba(6,214,160,0.2); color: var(--green); border: 1px solid rgba(6,214,160,0.3); }
.badge-classic { background: rgba(240,165,0,0.15); color: var(--gold); border: 1px solid rgba(240,165,0,0.3); }
.badge-premium { background: rgba(138,43,226,0.2); color: #bf7fff; border: 1px solid rgba(138,43,226,0.3); }

/* GALLERY */
.gallery {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px; margin-bottom: 24px;
}
.gallery-3 { grid-template-columns: repeat(3, 1fr); }
.gallery-4 { grid-template-columns: repeat(3, 1fr); }
.gallery-1 { grid-template-columns: 1fr; max-width: 500px; }
.gallery-4 .gallery-item { background: transparent !important; border: none !important; box-shadow: none !important; }
.gallery-4 .gallery-item .img-wrap { min-height: 160px; height: 160px; background: transparent !important; }
.gallery-4 .gallery-item img { height: 160px; min-height: 160px; object-fit: contain; }
.gallery-item {
  border-radius: 10px; overflow: hidden;
  background: var(--dark3); border: 1px solid rgba(255,255,255,0.06);
  cursor: pointer; transition: transform 0.2s, border-color 0.2s;
  display: flex; flex-direction: column;
}
.gallery-item:hover { transform: scale(1.02); border-color: rgba(240,165,0,0.4); }
.gallery-item .img-wrap {
  flex: 1; overflow: hidden;
  display: flex; align-items: center; justify-content: center;
  background: var(--dark3); min-height: 180px;
}
.gallery-item img {
  width: 100%; height: 100%;
  object-fit: contain; object-position: center;
  display: block; transition: transform 0.3s;
  min-height: 180px;
}
.gallery-item:hover img { transform: scale(1.04); }
.gallery-item span {
  display: block; text-align: center; font-size: 0.78rem;
  color: var(--text-muted); padding: 6px 8px; flex-shrink: 0;
}

/* PRODUCT FEATURES */
.product-features {
  display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 24px;
}
.product-features span {
  display: flex; align-items: center; gap: 6px;
  background: rgba(6,214,160,0.08); border: 1px solid rgba(6,214,160,0.2);
  color: var(--green); padding: 5px 12px; border-radius: 50px; font-size: 0.82rem;
}
.product-features i { font-size: 0.7rem; }

/* QUICK NAV */
.header-quicknav {
  border-top: 1px solid rgba(255,255,255,0.06);
  background: rgba(13,13,26,0.7);
}
.quicknav-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}
.quicknav-card {
  display: flex; align-items: center; gap: 16px;
  padding: 22px 28px;
  text-decoration: none; color: var(--text);
  border-right: 1px solid rgba(255,255,255,0.06);
  transition: background 0.2s;
}
.quicknav-card:last-child { border-right: none; }
.quicknav-card:hover { background: rgba(240,165,0,0.06); }
.quicknav-icon {
  width: 46px; height: 46px; border-radius: 12px; flex-shrink: 0;
  background: rgba(240,165,0,0.12); border: 1px solid rgba(240,165,0,0.2);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem; color: var(--gold);
  transition: background 0.2s;
}
.quicknav-card:hover .quicknav-icon { background: rgba(240,165,0,0.22); }
.quicknav-text { display: flex; flex-direction: column; gap: 2px; flex: 1; }
.quicknav-title { font-weight: 700; font-size: 0.95rem; }
.quicknav-sub { font-size: 0.78rem; color: var(--text-muted); }
.quicknav-arrow { color: var(--text-muted); font-size: 0.8rem; transition: transform 0.2s, color 0.2s; }
.quicknav-card:hover .quicknav-arrow { transform: translateX(4px); color: var(--gold); }
@media (max-width: 768px) {
  .quicknav-grid { grid-template-columns: 1fr; }
  .quicknav-card { border-right: none; border-bottom: 1px solid rgba(255,255,255,0.06); }
  .quicknav-card:last-child { border-bottom: none; }
}
.btn-demo {
  display: inline-flex; align-items: center; gap: 6px;
  background: linear-gradient(135deg, var(--gold), #e8920a);
  color: #000; padding: 7px 16px; border-radius: 8px;
  font-size: 0.85rem; font-weight: 700; text-decoration: none;
  transition: all 0.2s; white-space: nowrap;
}
.btn-demo:hover { background: linear-gradient(135deg, var(--gold-light), var(--gold)); transform: translateY(-1px); box-shadow: 0 6px 20px rgba(240,165,0,0.35); }
.btn-buy {
  display: inline-flex; align-items: center; gap: 8px;
  background: linear-gradient(135deg, var(--gold), #e8920a);
  color: #000; padding: 12px 28px; border-radius: 10px;
  font-weight: 700; text-decoration: none; font-size: 0.95rem;
  transition: all 0.2s;
}
.btn-buy:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(240,165,0,0.35); }

/* AUTOUPDATE GRID */
.autoupdate-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
@media (max-width: 900px) { .autoupdate-grid { grid-template-columns: 1fr; } }

.au-card {
  background: var(--card);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius); padding: 32px;
  transition: border-color 0.3s, box-shadow 0.3s;
}
.au-card:hover { border-color: rgba(240,165,0,0.3); box-shadow: 0 8px 40px rgba(240,165,0,0.08); }
.au-header { display: flex; align-items: flex-start; gap: 16px; margin-bottom: 24px; flex-wrap: wrap; }
.au-lang-badge {
  width: 52px; height: 52px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.85rem; font-weight: 800; flex-shrink: 0;
}
.au-lang-badge.csharp { background: rgba(104,33,122,0.3); color: #c792ea; border: 1px solid rgba(104,33,122,0.5); }
.au-lang-badge.cpp { background: rgba(0,89,179,0.3); color: #82aaff; border: 1px solid rgba(0,89,179,0.5); }
.au-header h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 4px; display: flex; align-items: center; gap: 8px; }
.au-header p { color: var(--text-muted); font-size: 0.88rem; }
.version-tag {
  font-size: 0.7rem; background: rgba(240,165,0,0.15);
  color: var(--gold); padding: 2px 8px; border-radius: 50px; font-weight: 600;
}
.au-features { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 20px 0; }
.au-feature-item {
  display: flex; align-items: flex-start; gap: 10px;
  background: rgba(255,255,255,0.03); border-radius: 10px; padding: 12px;
}
.au-feature-item > i { color: var(--gold); font-size: 1rem; margin-top: 2px; flex-shrink: 0; }
.au-feature-item strong { font-size: 0.85rem; display: block; margin-bottom: 2px; }
.au-feature-item p { font-size: 0.78rem; color: var(--text-muted); }

/* WHY GRID */
.why-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
@media (max-width: 768px) { .why-grid { grid-template-columns: repeat(2, 1fr); } }
.why-item {
  background: var(--card); border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius); padding: 28px 20px; text-align: center;
  transition: border-color 0.3s;
}
.why-item:hover { border-color: rgba(240,165,0,0.3); }
.why-item i { font-size: 2rem; color: var(--gold); margin-bottom: 14px; display: block; }
.why-item h4 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.why-item p { color: var(--text-muted); font-size: 0.85rem; }

/* CONTACT */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; max-width: 800px; margin: 0 auto; }
@media (max-width: 768px) { .contact-grid { grid-template-columns: repeat(1, 1fr); max-width: 360px; } }
.contact-card {
  border-radius: var(--radius); padding: 32px 20px; text-align: center;
  text-decoration: none; color: #fff; transition: transform 0.2s, box-shadow 0.2s;
  display: flex; flex-direction: column; align-items: center; gap: 8px;
}
.contact-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,0,0,0.3); }
.contact-card i { font-size: 2.2rem; margin-bottom: 4px; }
.contact-card h4 { font-size: 1.1rem; font-weight: 700; }
.contact-card p { font-size: 0.82rem; opacity: 0.8; }
.contact-card span {
  margin-top: 8px; font-size: 0.8rem; font-weight: 700;
  padding: 5px 14px; border-radius: 50px; background: rgba(255,255,255,0.15);
}
.contact-card.zalo { background: linear-gradient(135deg, #0068ff, #0050cc); }
.contact-card.facebook { background: linear-gradient(135deg, #1877f2, #0d5dbf); }
.contact-card.telegram { background: linear-gradient(135deg, #229ed9, #1a7fad); }
.contact-card.email { background: linear-gradient(135deg, #e94560, #c0392b); }

/* FOOTER */
.footer { background: var(--dark2); border-top: 1px solid rgba(255,255,255,0.06); padding: 40px 0; text-align: center; }
.footer-inner { display: flex; flex-direction: column; align-items: center; gap: 10px; }
.footer .logo { font-size: 1.3rem; }
.footer p { color: var(--text-muted); font-size: 0.88rem; }
.footer .copy { font-size: 0.8rem; margin-top: 6px; }

/* LIGHTBOX */
.lightbox {
  display: none; position: fixed; inset: 0; z-index: 999;
  background: rgba(0,0,0,0.92); align-items: center; justify-content: center;
}
.lightbox.active { display: flex; }
.lightbox img { max-width: 90vw; max-height: 90vh; border-radius: 10px; }
.lightbox-close {
  position: absolute; top: 20px; right: 28px;
  font-size: 2rem; color: #fff; cursor: pointer; opacity: 0.7;
}
.lightbox-close:hover { opacity: 1; }

/* RESPONSIVE */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .hero-stats { gap: 28px; }
  .product-header { flex-direction: column; }
  .product-price { margin-left: 0; }
  .gallery { grid-template-columns: 1fr; }
  .gallery-3 { grid-template-columns: 1fr; }
  .au-features { grid-template-columns: 1fr; }
}
.gallery-au { grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); }

/* TÀI NGUYÊN TABS */
.tn-tabs {
  display: flex; gap: 10px; flex-wrap: wrap;
  margin-bottom: 24px;
}
.tn-tab {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 20px; border-radius: 50px;
  border: 1px solid rgba(255,255,255,0.1);
  background: rgba(255,255,255,0.04);
  color: var(--text-muted); font-size: 0.88rem; font-weight: 600;
  cursor: pointer; transition: all 0.2s;
}
.tn-tab:hover { border-color: rgba(240,165,0,0.4); color: var(--gold); }
.tn-tab.active {
  background: rgba(240,165,0,0.15);
  border-color: rgba(240,165,0,0.5);
  color: var(--gold);
}
.tn-content { min-height: 160px; }
.tn-panel { display: none; }
.tn-panel.active { display: block; }
.tn-drive-btn {
  display: flex; align-items: center; gap: 20px;
  background: var(--card); border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius); padding: 24px 28px;
  text-decoration: none; color: var(--text);
  transition: all 0.2s; max-width: 600px;
}
.tn-drive-btn:hover {
  border-color: rgba(240,165,0,0.4);
  background: var(--card2);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}
.tn-drive-btn .fa-google-drive { font-size: 2.2rem; color: #4285f4; flex-shrink: 0; }
.tn-drive-btn div { flex: 1; }
.tn-drive-btn strong { display: block; font-size: 1rem; font-weight: 700; margin-bottom: 4px; }
.tn-drive-btn span { font-size: 0.82rem; color: var(--text-muted); }
.tn-drive-btn .fa-arrow-up-right-from-square { color: var(--text-muted); font-size: 0.9rem; }
.tn-note {
  margin-top: 14px; font-size: 0.82rem;
  color: var(--text-muted); display: flex; align-items: center; gap: 6px;
}
.tn-note i { color: var(--gold); }

/* NAV DROPDOWN */
.nav-dropdown { position: relative; }
.nav-dropdown-btn {
  cursor: pointer; border: none; font-family: inherit; font-size: 0.95rem;
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 20px;
}
.nav-dropdown-menu {
  display: none; position: absolute; top: calc(100% + 10px); left: 0;
  background: rgba(13,13,26,0.98); border: 1px solid rgba(240,165,0,0.25);
  border-radius: 10px; min-width: 200px; overflow: visible;
  box-shadow: 0 12px 32px rgba(0,0,0,0.4); z-index: 200;
  backdrop-filter: blur(12px);
}
.nav-dropdown.open .nav-dropdown-menu { display: block; }
.nav-dropdown-menu a {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 18px; color: var(--text); text-decoration: none;
  font-size: 0.88rem; font-weight: 500; transition: background 0.15s, color 0.15s;
}
.nav-dropdown-menu a:hover { background: rgba(240,165,0,0.1); color: var(--gold); }
.nav-dropdown-menu a i { width: 16px; color: var(--gold); }

/* MODAL CẢNH BÁO TÀI NGUYÊN */
.tn-modal {
  display: none; position: fixed; inset: 0; z-index: 999;
  background: rgba(0,0,0,0.75); align-items: center; justify-content: center;
  backdrop-filter: blur(4px);
}
.tn-modal.active { display: flex; }
.tn-modal-box {
  background: var(--card); border: 1px solid rgba(240,165,0,0.3);
  border-radius: 16px; padding: 40px 36px; max-width: 420px; width: 90%;
  text-align: center; box-shadow: 0 20px 60px rgba(0,0,0,0.5);
  animation: modalIn 0.25s ease;
}
@keyframes modalIn {
  from { transform: scale(0.9); opacity: 0; }
  to   { transform: scale(1);   opacity: 1; }
}
.tn-modal-icon { font-size: 3rem; color: #f59e0b; margin-bottom: 16px; }
.tn-modal-box h3 { font-size: 1.2rem; font-weight: 800; margin-bottom: 14px; color: #fff; }
.tn-modal-box p { color: var(--text-muted); font-size: 0.9rem; margin-bottom: 8px; line-height: 1.6; }
.tn-modal-box p strong { color: #f87171; }
.tn-modal-actions { display: flex; gap: 12px; margin-top: 24px; justify-content: center; }
.tn-modal-cancel {
  padding: 10px 24px; border-radius: 8px; border: 1px solid rgba(255,255,255,0.15);
  background: transparent; color: var(--text-muted); font-size: 0.9rem;
  cursor: pointer; font-family: inherit; transition: all 0.2s;
}
.tn-modal-cancel:hover { border-color: rgba(255,255,255,0.3); color: #fff; }
.tn-modal-confirm {
  padding: 10px 24px; border-radius: 8px; border: none;
  background: linear-gradient(135deg, var(--gold), #e8920a);
  color: #000; font-weight: 700; font-size: 0.9rem;
  cursor: pointer; font-family: inherit; transition: all 0.2s;
  display: inline-flex; align-items: center; gap: 6px;
}
.tn-modal-confirm:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(240,165,0,0.35); }

/* UNPACK CONTACT */
.unpack-contact {
  display: flex; gap: 24px; flex-wrap: wrap;
  margin-top: 20px; padding-top: 20px;
  border-top: 1px solid rgba(255,255,255,0.06);
}
.unpack-contact-item {
  display: flex; align-items: center; gap: 12px;
  background: rgba(255,255,255,0.03); border-radius: 10px;
  padding: 12px 18px; flex: 1; min-width: 220px;
}
.unpack-contact-item > i { font-size: 1.6rem; flex-shrink: 0; }
.unpack-contact-item span { font-size: 0.75rem; color: var(--text-muted); display: block; }
.unpack-contact-item strong { font-size: 0.95rem; color: var(--text); }
.unpack-contact-item a { font-size: 0.9rem; color: var(--gold); text-decoration: none; }
.unpack-contact-item a:hover { text-decoration: underline; }