:root {
  --navy: #1f2d3d;
  --brand: #1B2071;       /* màu nền logo */
  --orange: #F5921F;
  --text: #55636f;
  --bg-soft: #f5f8fb;
  --border: #e3e8ee;
  --white: #ffffff;
  --maxw: 1100px;
}

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

html { scroll-behavior: smooth; }

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

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: var(--white);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 72px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-bolt { color: var(--orange); font-size: 22px; }
.brand-name { font-weight: 800; letter-spacing: .5px; color: var(--brand); font-size: 18px; }
.nav { display: flex; gap: 22px; }
.nav a { color: var(--text); font-weight: 600; font-size: 15px; }
.nav a:hover { color: var(--orange); }

/* ===== Hero ===== */
.hero {
  background: linear-gradient(135deg, var(--brand) 0%, #11143f 100%);
  padding: 64px 0;
}
.hero-inner { display: flex; align-items: center; gap: 44px; }
.hero-text { flex: 1; }
.hero-logo { width: 360px; max-width: 42%; height: auto; flex-shrink: 0; border-radius: 8px; }
.hero-brand { font-size: 44px; font-weight: 900; color: var(--white); letter-spacing: 1px; line-height: 1.1; }
.hero-slogan {
  color: var(--orange); font-weight: 900;
  font-size: 32px; line-height: 1.2; margin: 12px 0 20px; letter-spacing: .6px;
  text-shadow: 0 2px 18px rgba(245,146,31,.45);
}
.hero-sub { font-size: 17px; color: #c8cfe6; max-width: 560px; margin-bottom: 26px; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; }

.btn { display: inline-block; padding: 13px 22px; border-radius: 8px; font-weight: 700; font-size: 16px; }
.btn-primary { background: var(--orange); color: var(--white); }
.btn-primary:hover { filter: brightness(.95); }
.btn-outline { border: 1.5px solid #fff; color: #fff; }
.btn-outline:hover { background: #fff; color: var(--brand); }
.btn-fb { background: #1877f2; color: #fff; font-size: 15px; padding: 11px 18px; }
.btn-fb:hover { filter: brightness(.95); }

/* ===== Sections ===== */
.section { padding: 56px 0; }
.section-alt { background: var(--bg-soft); }
.section-title { font-size: 28px; font-weight: 800; color: var(--navy); text-align: center; margin-bottom: 16px; }
.section-sub { text-align: center; color: var(--text); max-width: 720px; margin: 0 auto 30px; font-size: 16px; }

/* ===== Vì sao ===== */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.feature-card { background: var(--bg-soft); border-radius: 12px; padding: 26px 22px; }
.feature-icon { font-size: 32px; margin-bottom: 10px; }
.feature-card h3 { color: var(--navy); font-size: 18px; margin-bottom: 6px; }
.feature-card p { color: var(--text); font-size: 15px; }

/* ===== Dịch vụ & giá ===== */
.price-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.price-card { background: var(--white); border: 1px solid var(--border); border-radius: 12px; padding: 28px; }
.price-card h3 { color: var(--navy); font-size: 20px; margin-bottom: 10px; }
.price-desc { color: var(--text); font-size: 15px; margin-bottom: 16px; }
.price-value { color: var(--orange); font-weight: 800; font-size: 22px; }
.price-note { color: var(--text); font-size: 13px; text-align: center; margin-top: 18px; font-style: italic; }

/* ===== Quy trình ===== */
.process-figure {
  max-width: 860px; margin: 0 auto 28px; border: 1px solid var(--border);
  border-radius: 12px; overflow: hidden; background: var(--white); cursor: zoom-in;
}
.process-figure img { width: 100%; height: auto; display: block; }
.process-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; }
.process-step { background: var(--white); border: 1px solid var(--border); border-radius: 12px; padding: 24px 14px 16px; position: relative; }
.process-num { position: absolute; top: -16px; left: 14px; width: 34px; height: 34px; background: var(--orange); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 800; }
.process-step h3 { color: var(--navy); font-size: 16px; margin: 4px 0 6px; }
.process-step p { color: var(--text); font-size: 13px; }

/* ===== Tiêu chuẩn ===== */
.spec-strip { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-bottom: 30px; }
.spec-item { background: var(--brand); color: #fff; border-radius: 12px; padding: 18px 14px; text-align: center; }
.spec-item strong { display: block; font-size: 26px; color: var(--orange); }
.spec-item span { font-size: 13px; color: #c8cfe6; }
.standards-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.standard-card { background: var(--white); border: 1px solid var(--border); border-radius: 12px; padding: 24px; }
.standard-tag { display: inline-block; background: #fdeedd; color: var(--orange); font-weight: 700; font-size: 12px; padding: 4px 10px; border-radius: 20px; margin-bottom: 10px; }
.standard-card h3 { color: var(--navy); font-size: 19px; margin-bottom: 8px; }
.standard-card p { color: var(--text); font-size: 14px; margin-bottom: 10px; }
.standard-card ul { list-style: none; }
.standard-card li { color: var(--text); font-size: 14px; padding-left: 22px; position: relative; margin-bottom: 6px; }
.standard-card li::before { content: "✓"; position: absolute; left: 0; color: var(--orange); font-weight: 800; }
.cert-figure { max-width: 460px; margin: 28px auto 0; border: 1px solid var(--border); border-radius: 12px; overflow: hidden; background: var(--white); }
.cert-figure img { width: 100%; height: auto; cursor: zoom-in; }
.cert-figure figcaption { padding: 12px 16px; text-align: center; color: var(--text); font-size: 14px; }

/* ===== Sản phẩm ===== */
.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; max-width: 820px; margin: 0 auto; }
.product-card { background: var(--white); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; }
.product-card img { width: 100%; height: 180px; object-fit: cover; }
.product-card figcaption { padding: 12px; text-align: center; font-weight: 600; color: var(--navy); font-size: 15px; }

/* ===== Công trình tiêu biểu ===== */
.project-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.project-card {
  display: block; text-align: left; padding: 0; border: 1px solid var(--border);
  background: var(--white); border-radius: 14px; overflow: hidden; cursor: pointer;
  font: inherit; color: inherit; transition: transform .15s, box-shadow .15s;
}
.project-card:hover { transform: translateY(-3px); box-shadow: 0 10px 24px rgba(27,32,113,.14); }
.project-thumb { position: relative; aspect-ratio: 4 / 3; background: #eef1f6; }
.project-thumb img { width: 100%; height: 100%; object-fit: cover; }
.project-count {
  position: absolute; right: 10px; bottom: 10px; background: rgba(17,20,63,.82);
  color: #fff; font-size: 12px; font-weight: 600; padding: 4px 10px; border-radius: 20px;
}
.project-info { padding: 14px 16px; }
.project-info h3 { color: var(--navy); font-size: 16px; margin-bottom: 2px; }
.project-info p { color: var(--text); font-size: 13px; }

/* ===== Slider ngang (video, bài viết) ===== */
.slider { position: relative; }
.slider-track {
  display: flex; gap: 16px; overflow-x: auto; scroll-snap-type: x mandatory;
  padding: 4px 2px 14px; scrollbar-width: thin; -webkit-overflow-scrolling: touch;
}
.slide { flex: 0 0 320px; max-width: 80vw; scroll-snap-align: start; }
.slider-arrow {
  position: absolute; top: 38%; transform: translateY(-50%); z-index: 5;
  width: 44px; height: 44px; border-radius: 50%; border: none; cursor: pointer;
  background: var(--white); color: var(--brand); font-size: 26px; line-height: 1;
  box-shadow: 0 3px 12px rgba(0,0,0,.18);
}
.slider-arrow:hover { background: var(--brand); color: #fff; }
.slider-arrow:disabled { opacity: .35; cursor: default; }
.slider-prev { left: -10px; }
.slider-next { right: -10px; }

.slide-video .video-cover {
  position: relative; aspect-ratio: 16 / 10; border-radius: 12px; overflow: hidden;
  cursor: pointer; background: #000;
}
.video-cover img { width: 100%; height: 100%; object-fit: cover; opacity: .92; }
.play-icon {
  position: absolute; inset: 0; margin: auto; width: 56px; height: 56px;
  display: flex; align-items: center; justify-content: center;
  background: rgba(245,146,31,.92); color: #fff; border-radius: 50%; font-size: 22px;
  padding-left: 4px;
}
.slide-cap { margin-top: 8px; font-size: 14px; font-weight: 600; color: var(--navy); }

/* ===== Bài viết Facebook ===== */
.posts-head { display: flex; align-items: center; justify-content: center; gap: 16px; flex-wrap: wrap; }
.post-card { background: var(--white); border: 1px solid var(--border); border-radius: 14px; overflow: hidden; display: flex; flex-direction: column; cursor: pointer; transition: transform .15s, box-shadow .15s; }
.post-card:hover { transform: translateY(-3px); box-shadow: 0 10px 24px rgba(27,32,113,.14); }
.post-media { position: relative; aspect-ratio: 4 / 3; background: #eef1f6; }
.post-media img { width: 100%; height: 100%; object-fit: cover; }
.post-mcount { position: absolute; right: 10px; bottom: 10px; background: rgba(17,20,63,.82); color: #fff; font-size: 12px; font-weight: 600; padding: 4px 10px; border-radius: 20px; }
.post-body { padding: 16px; }
.post-date { font-size: 12px; color: var(--orange); font-weight: 700; }
.post-text { color: var(--navy); font-size: 14px; margin: 6px 0 12px; display: -webkit-box; -webkit-line-clamp: 5; -webkit-box-orient: vertical; overflow: hidden; }
.post-link { color: #1877f2; font-weight: 700; font-size: 14px; }
.posts-empty { color: var(--text); padding: 20px; }

/* ===== Modal đọc bài viết ===== */
.post-modal { position: fixed; inset: 0; z-index: 110; background: rgba(0,0,0,.6); display: none; align-items: flex-start; justify-content: center; padding: 40px 16px; overflow-y: auto; }
.post-modal.open { display: flex; }
.post-modal-panel { position: relative; background: var(--white); border-radius: 14px; max-width: 640px; width: 100%; padding: 28px; }
.post-modal-close { position: absolute; top: 12px; right: 12px; width: 38px; height: 38px; border-radius: 50%; border: none; background: var(--bg-soft); color: var(--navy); font-size: 18px; cursor: pointer; }
.post-modal-close:hover { background: var(--border); }
.post-modal-date { font-size: 13px; color: var(--orange); font-weight: 700; }
.post-modal-text { margin: 10px 0 18px; }
.post-modal-text p { color: var(--navy); font-size: 15px; margin-bottom: 12px; white-space: pre-wrap; }
.post-modal-media { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-bottom: 20px; }
.post-thumb { position: relative; aspect-ratio: 1 / 1; border-radius: 10px; overflow: hidden; cursor: pointer; background: #000; }
.post-thumb img { width: 100%; height: 100%; object-fit: cover; }
.post-thumb:hover img { opacity: .85; }
.post-thumb .play-icon { width: 44px; height: 44px; font-size: 18px; }
.post-modal-fb { display: inline-block; }

/* ===== Cảm nhận khách hàng ===== */
.review-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.review-card { background: var(--white); border: 1px solid var(--border); border-radius: 14px; padding: 24px; display: flex; flex-direction: column; }
.review-stars { color: var(--orange); font-size: 18px; letter-spacing: 2px; margin-bottom: 12px; }
.review-card blockquote { color: var(--navy); font-size: 15px; font-style: italic; line-height: 1.65; flex: 1; margin-bottom: 16px; }
.review-card blockquote::before { content: "“"; color: var(--orange); font-size: 26px; font-weight: 800; margin-right: 2px; }
.review-card figcaption { border-top: 1px solid var(--border); padding-top: 12px; }
.review-card figcaption strong { display: block; color: var(--navy); font-size: 15px; }
.review-card figcaption span { color: var(--text); font-size: 13px; }

/* ===== Footer ===== */
.footer { background: var(--brand); color: #c8cfe6; padding: 48px 0 0; }
.footer-inner { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: 28px; }
.footer-name { color: #fff; font-size: 22px; font-weight: 900; letter-spacing: .5px; }
.footer-slogan { color: var(--orange); font-weight: 700; margin: 4px 0 14px; }
.footer-fb { display: inline-block; background: #1877f2; color: #fff; font-weight: 700; padding: 8px 16px; border-radius: 8px; font-size: 14px; }
.footer-col h4 { color: var(--white); margin-bottom: 12px; font-size: 16px; }
.footer-col p { margin-bottom: 8px; font-size: 15px; }
.footer-col a:hover { color: var(--orange); }
.footer-bottom { text-align: center; padding: 20px; margin-top: 32px; border-top: 1px solid #ffffff22; font-size: 14px; }

/* ===== Nút nổi ===== */
.float-btn {
  position: fixed; right: 18px; z-index: 60;
  width: 52px; height: 52px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px; color: var(--white);
  box-shadow: 0 4px 12px rgba(0,0,0,.25);
}
.float-call { bottom: 84px; background: var(--orange); }
.float-zalo { bottom: 22px; background: #0068ff; }

/* ===== Lightbox / carousel ===== */
.lightbox { position: fixed; inset: 0; z-index: 100; background: rgba(0,0,0,.92); display: none; align-items: center; justify-content: center; }
.lightbox.open { display: flex; }
.lightbox-stage { display: flex; align-items: center; justify-content: center; max-width: 92vw; max-height: 88vh; }
.lightbox-media { max-width: 92vw; max-height: 88vh; border-radius: 6px; }
video.lightbox-media { width: auto; background: #000; }
.lightbox button { position: absolute; background: rgba(255,255,255,.12); color: #fff; border: none; cursor: pointer; line-height: 1; }
.lightbox-close { top: 18px; right: 18px; width: 46px; height: 46px; border-radius: 50%; font-size: 22px; }
.lightbox-prev, .lightbox-next { top: 50%; transform: translateY(-50%); width: 54px; height: 64px; font-size: 38px; border-radius: 8px; }
.lightbox-prev { left: 14px; }
.lightbox-next { right: 14px; }
.lightbox button:hover { background: rgba(255,255,255,.28); }
.lightbox-count { position: absolute; bottom: 18px; left: 50%; transform: translateX(-50%); background: rgba(0,0,0,.5); color: #fff; padding: 4px 14px; border-radius: 20px; font-size: 14px; }

/* ===== Responsive ===== */
@media (max-width: 1000px) {
  .standards-grid { grid-template-columns: 1fr; }
  .process-grid { grid-template-columns: repeat(2, 1fr); }
  .project-grid { grid-template-columns: repeat(2, 1fr); }
  .review-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 900px) {
  .product-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 860px) {
  .brand-name { font-size: 15px; }
  .nav { gap: 14px; overflow-x: auto; -webkit-overflow-scrolling: touch; }
  .nav a { white-space: nowrap; }
}
@media (max-width: 760px) {
  .feature-grid, .price-grid, .spec-strip, .footer-inner { grid-template-columns: 1fr; }
  .spec-strip { grid-template-columns: repeat(2, 1fr); }
  .hero { padding: 40px 0; }
  .hero-inner { flex-direction: column-reverse; gap: 24px; text-align: center; }
  .hero-logo { width: 260px; max-width: 78%; }
  .hero-sub { font-size: 16px; margin-left: auto; margin-right: auto; }
  .hero-brand { font-size: 30px; }
  .hero-slogan { font-size: 24px; }
  .hero-cta { justify-content: center; }
  .btn { width: 100%; text-align: center; }
  .btn-fb, .footer-fb { width: auto; }
  .process-grid { grid-template-columns: 1fr; }
  .slider-prev { left: 0; }
  .slider-next { right: 0; }
}
@media (max-width: 640px) {
  .header-inner { height: 64px; }
  .brand-name { font-size: 13px; }
  .nav a { font-size: 13px; }
  .project-grid { grid-template-columns: 1fr; }
  .review-grid { grid-template-columns: 1fr; }
  .lightbox-prev, .lightbox-next { width: 42px; font-size: 30px; }
}
@media (max-width: 480px) {
  .product-grid { grid-template-columns: 1fr; }
}