:root {
  --primary: #b8893b;
  --primary-dark: #9a7130;
  --dark: #14202e;
  --text: #3a4250;
  --muted: #6b7280;
  --bg: #ffffff;
  --bg-alt: #f6f4ef;
  --radius: 12px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 16px; }

h1, h2, h3 { color: var(--dark); line-height: 1.25; }
h2 { font-size: clamp(1.5rem, 3.5vw, 2rem); margin-bottom: 12px; text-align: center; }
.sub { text-align: center; color: var(--muted); max-width: 680px; margin: 0 auto 36px; }

/* Nút */
.btn {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  padding: 14px 28px;
  border: 2px solid var(--primary);
  border-radius: 999px;
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  cursor: pointer;
  transition: background .2s;
}
.btn:hover { background: var(--primary-dark); border-color: var(--primary-dark); }
.btn-small { padding: 8px 18px; color: #fff !important; }
.btn-ghost { background: transparent; border-color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); border-color: #fff; }

/* Điều hướng */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(255,255,255,.96);
  border-bottom: 1px solid #eee;
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-size: 1.4rem; font-weight: 800; color: var(--dark); text-decoration: none; }
.logo span { color: var(--primary); }
.nav nav { display: flex; align-items: center; gap: 24px; }
.nav nav a { color: var(--text); text-decoration: none; font-weight: 500; }

/* Hero */
.hero {
  background:
    linear-gradient(rgba(20,32,46,.72), rgba(20,32,46,.82)),
    url("images/tong-the.jpg") center/cover;
  color: #fff;
  text-align: center;
  padding: 88px 0 96px;
}
.eyebrow { color: #e6c88f; font-weight: 600; letter-spacing: .02em; margin-bottom: 12px; }
.hero h1 { color: #fff; font-size: clamp(2rem, 5.5vw, 3.4rem); margin-bottom: 16px; }
.hero h1 span { display: block; font-size: .55em; font-weight: 600; color: #e6c88f; margin-top: 8px; }
.lead { font-size: 1.15rem; opacity: .92; max-width: 720px; margin: 0 auto 36px; }
.lead strong { color: #fff; }
.hero-cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* Giá */
.price-tag {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  border-radius: var(--radius);
  padding: 12px 28px;
  margin-bottom: 28px;
  font-size: 1.15rem;
}
.price-tag b { font-size: 2rem; margin: 0 4px; }
.price-tag small { display: block; font-size: .85rem; opacity: .9; }

/* Chỉ số */
.stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  max-width: 860px;
  margin: 0 auto 36px;
}
.stats li {
  background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.18);
  border-radius: var(--radius);
  padding: 16px 8px;
}
.stats b { display: block; font-size: clamp(1.4rem, 3.5vw, 2rem); color: #e6c88f; }
.stats span { font-size: .9rem; opacity: .9; }

/* Section */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }
.section-dark { background: var(--dark); color: #fff; text-align: center; }
.section-dark h2 { color: #fff; margin-bottom: 32px; }
.stats-dark { margin-bottom: 20px; }
.note { opacity: .85; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin-top: 32px;
}
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }

/* Lý do */
.feature {
  background: #fff;
  border: 1px solid #ece8df;
  border-radius: var(--radius);
  padding: 24px;
}
.num { font-weight: 800; color: var(--primary); font-size: 1.4rem; margin-bottom: 6px; }
.feature h3 { margin-bottom: 6px; font-size: 1.1rem; }
.feature p { color: var(--muted); }

/* Sản phẩm */
.product { display: grid; grid-template-columns: 1fr 1.4fr; gap: 24px; align-items: start; }
.spec {
  width: 100%;
  background: #fff;
  border-radius: var(--radius);
  border-collapse: collapse;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0,0,0,.05);
}
.spec caption { text-align: left; font-weight: 600; color: var(--dark); padding-bottom: 8px; }
.spec th, .spec td { padding: 12px 16px; border-bottom: 1px solid #eee; text-align: left; }
.spec td { text-align: right; font-weight: 600; }
.spec .total th, .spec .total td { background: var(--primary); color: #fff; border: none; }
.layouts { display: grid; gap: 16px; }
.layout { background: #fff; border-radius: var(--radius); padding: 20px 24px; border-left: 4px solid var(--primary); }
.layout h3 { margin-bottom: 8px; font-size: 1.05rem; }
.layout ul { list-style: none; display: grid; gap: 4px; }

/* Ảnh & video */
.video {
  position: relative; aspect-ratio: 16 / 9;
  border-radius: var(--radius); overflow: hidden;
  background: #000; margin-bottom: 20px;
  box-shadow: 0 8px 30px rgba(0,0,0,.12);
}
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.gallery { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 24px; }
.gallery-4 { grid-template-columns: repeat(4, 1fr); }
.gallery img {
  width: 100%; aspect-ratio: 3 / 2; object-fit: cover;
  border-radius: var(--radius); display: block;
}
.plan img { width: 100%; border-radius: var(--radius); box-shadow: 0 4px 20px rgba(0,0,0,.08); display: block; }

/* Vị trí */
.box { background: var(--bg-alt); border-radius: var(--radius); padding: 24px; }
.box h3 { margin-bottom: 12px; }
.times { list-style: none; }
.times li {
  display: flex; justify-content: space-between; gap: 12px;
  padding: 10px 0; border-bottom: 1px dashed #d9d4c8;
}
.times li:last-child { border-bottom: none; }
.times b { color: var(--primary); white-space: nowrap; }

/* Liên hệ */
.contact { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }
.contact h2 { text-align: left; }
.contact-info { list-style: none; margin-top: 20px; display: grid; gap: 8px; }
.contact-info a { color: var(--dark); font-weight: 600; }

.form { display: grid; gap: 12px; background: #fff; padding: 24px; border-radius: var(--radius); box-shadow: 0 4px 20px rgba(0,0,0,.06); }
.form input, .form select {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid #d6d3cc;
  border-radius: 8px;
  font: inherit;
}
.form input:focus, .form select:focus { outline: 2px solid var(--primary); border-color: transparent; }
.form-msg { color: #15803d; font-weight: 600; }

/* FAQ */
.faq { max-width: 780px; }
.faq h2 { margin-bottom: 24px; }
.faq details { border-bottom: 1px solid #eee; padding: 14px 0; }
.faq summary { cursor: pointer; font-weight: 600; color: var(--dark); }
.faq details p { margin-top: 8px; color: var(--muted); }
.faq a { color: var(--primary); }

/* Footer */
.footer { background: var(--dark); color: #cbd0d8; text-align: center; padding: 28px 0; font-size: .9rem; }
.footer p + p { margin-top: 8px; }
.disclaimer { font-size: .8rem; opacity: .75; max-width: 760px; margin-left: auto; margin-right: auto; }

/* Thanh gọi nhanh */
.mobile-bar { display: none; }

@media (max-width: 760px) {
  .nav nav a:not(.btn) { display: none; }
  .hero { padding: 56px 0 64px; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 52px 0; }
  .product, .grid-2, .contact { grid-template-columns: 1fr; gap: 20px; }
  .gallery, .gallery-4 { grid-template-columns: 1fr 1fr; }
  .gallery > :first-child:nth-last-child(3) { grid-column: 1 / -1; }
  .footer { padding-bottom: 80px; }
  .mobile-bar {
    display: grid; grid-template-columns: 1fr 1fr;
    position: fixed; left: 0; right: 0; bottom: 0; z-index: 20;
  }
  .mobile-bar a {
    text-align: center; padding: 14px; font-weight: 700;
    text-decoration: none; color: #fff; background: var(--dark);
  }
  .mobile-bar a:last-child { background: var(--primary); }
}