/* ==========================================================================
   SOLARBUILD — Design system
   Tông màu: xanh năng lượng + xám bê tông
   Tất cả biến giao diện gom ở :root để chỉnh nhanh.
   ========================================================================== */

:root {
  /* Màu thương hiệu */
  --brand-800: #5c0011;
  --brand-700: #c2002b;
  --brand-600: #ee0033;
  --brand-500: #ff2e52;
  --brand-400: #ff6b83;
  --brand-100: #ffe5ea;
  --brand-50: #fff5f7;

  --solar: #ffb703;
  --solar-600: #e09f00;
  --solar-soft: #fff4d6;

  /* Trung tính / bê tông */
  --ink: #171217;
  --ink-2: #3a3238;
  --muted: #6f6469;
  --line: #e9e3e6;
  --line-strong: #d8d0d4;
  --bg: #ffffff;
  --bg-soft: #f8f5f6;
  --bg-dark: #140f12;

  /* Hệ thống */
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 22px;
  --radius-pill: 999px;
  --shadow-sm: 0 1px 2px rgba(12, 22, 19, .06), 0 1px 3px rgba(12, 22, 19, .04);
  --shadow: 0 6px 24px rgba(12, 22, 19, .07);
  --shadow-lg: 0 20px 60px rgba(12, 22, 19, .12);
  --ring: 0 0 0 4px rgba(238, 0, 51, .16);

  --container: 1180px;
  --header-h: 74px;

  --font: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto,
          "Helvetica Neue", Arial, "Noto Sans", sans-serif;
}

/* --------------------------------------------------------------------------
   Reset
   -------------------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16.5px;
  line-height: 1.65;
  color: var(--ink-2);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; display: block; }
a { color: var(--brand-600); text-decoration: none; }
a:hover { color: var(--brand-700); }
button { font: inherit; color: inherit; cursor: pointer; }
input, select, textarea { font: inherit; color: inherit; }
h1, h2, h3, h4 { color: var(--ink); line-height: 1.18; margin: 0 0 .6em; letter-spacing: -.02em; }
h1 { font-size: clamp(2rem, 4.6vw, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.55rem, 3vw, 2.35rem); font-weight: 800; }
h3 { font-size: clamp(1.12rem, 1.6vw, 1.32rem); font-weight: 700; }
p { margin: 0 0 1em; }
ul, ol { margin: 0 0 1em; padding-left: 1.2em; }
strong { color: var(--ink); font-weight: 700; }

::selection { background: var(--brand-400); color: #3d0009; }

:focus-visible {
  outline: 3px solid var(--brand-500);
  outline-offset: 2px;
  border-radius: 4px;
}

/* --------------------------------------------------------------------------
   Layout helpers
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 22px;
}
.container-narrow { max-width: 860px; }

.section { padding: clamp(56px, 8vw, 104px) 0; }
.section-tight { padding: clamp(40px, 5vw, 64px) 0; }
.section-soft { background: var(--bg-soft); }
.section-dark { background: var(--bg-dark); color: #d9cfd3; }
.section-dark h1, .section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }

.section-head { max-width: 720px; margin-bottom: clamp(28px, 4vw, 46px); }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head p { color: var(--muted); font-size: 1.05rem; margin-bottom: 0; }
.section-dark .section-head p { color: #b3a6ab; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--brand-700);
  margin-bottom: 14px;
}
.eyebrow::before {
  content: "";
  width: 22px; height: 2px;
  background: currentColor;
  border-radius: 2px;
}
.section-dark .eyebrow { color: var(--brand-400); }

.lead { font-size: 1.09rem; color: var(--muted); }

.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-auto { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }

.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mt-24 { margin-top: 24px; }
.mt-40 { margin-top: 40px; }
.mb-0 { margin-bottom: 0; }

.skip-link {
  position: absolute;
  left: 16px; top: -60px;
  z-index: 200;
  background: var(--brand-700);
  color: #fff;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  transition: top .2s;
}
.skip-link:focus { top: 12px; color: #fff; }

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
  --btn-bg: var(--brand-600);
  --btn-fg: #fff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-size: .95rem;
  font-weight: 650;
  line-height: 1.2;
  text-align: center;
  transition: transform .16s ease, box-shadow .2s ease, background .2s ease, border-color .2s ease;
  white-space: nowrap;
}
.btn:hover { color: var(--btn-fg); transform: translateY(-1px); box-shadow: 0 10px 24px rgba(238, 0, 51, .22); }
.btn:active { transform: translateY(0); }
.btn svg { width: 18px; height: 18px; flex: none; }

.btn-primary { --btn-bg: var(--brand-600); }
.btn-primary:hover { --btn-bg: var(--brand-700); }

.btn-solar { --btn-bg: var(--solar); --btn-fg: #2a1d00; }
.btn-solar:hover { --btn-bg: #ff2e52; box-shadow: 0 10px 24px rgba(255, 183, 3, .35); }

.btn-ghost {
  --btn-bg: transparent;
  --btn-fg: var(--ink);
  border-color: var(--line-strong);
  font-weight: 600;
}
.btn-ghost:hover { --btn-bg: var(--bg-soft); box-shadow: none; border-color: var(--brand-500); }

.btn-light {
  --btn-bg: rgba(255, 255, 255, .1);
  --btn-fg: #fff;
  border-color: rgba(255, 255, 255, .28);
  backdrop-filter: blur(6px);
}
.btn-light:hover { --btn-bg: rgba(255, 255, 255, .18); box-shadow: none; }

.btn-block { width: 100%; }
.btn-sm { padding: 10px 16px; font-size: .875rem; }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-weight: 650;
  color: var(--brand-700);
}
.link-arrow svg { width: 16px; height: 16px; transition: transform .2s ease; }
.link-arrow:hover svg { transform: translateX(4px); }

/* --------------------------------------------------------------------------
   Header & navigation
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .88);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s, box-shadow .2s, background .2s;
}
.site-header.is-stuck {
  border-bottom-color: var(--line);
  box-shadow: 0 6px 20px rgba(12, 22, 19, .05);
}

.header-inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 18px;
}

.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); }
.brand:hover { color: var(--ink); }
.brand-mark {
  width: 42px; height: 42px;
  flex: none;
  border-radius: 12px;
  background: linear-gradient(145deg, var(--brand-600), var(--brand-800));
  display: grid;
  place-items: center;
  box-shadow: 0 4px 12px rgba(226, 0, 45, .24);
}
.brand-mark svg { width: 24px; height: 24px; }

/* Logo dạng ảnh (Viettel wordmark) */
img.brand-mark {
  width: auto;
  height: 34px;
  background: none;
  box-shadow: none;
  border-radius: 0;
  flex: none;
}
.site-footer img.brand-mark { height: 30px; }

/* --------------------------------------------------------------------------
   LOGO CHÍNH THỨC
   Header/footer đang dùng assets/img/logo-viettel.png (wordmark tạm, nền trong suốt).
   Có file logo chính thức do Viettel cấp: ghi đè đúng tên file đó (cao >= 108px,
   nền trong suốt) — không cần sửa HTML/CSS. Muốn đổi chiều cao thì sửa img.brand-mark.
   -------------------------------------------------------------------------- */
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong {
  font-size: clamp(.92rem, 1.4vw, 1.06rem);
  font-weight: 800;
  letter-spacing: .035em;
  text-transform: uppercase;
  white-space: nowrap;
}
.brand-text small {
  font-size: .68rem;
  color: var(--muted);
  letter-spacing: .02em;
  font-weight: 500;
}

.nav { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.nav a {
  position: relative;
  padding: 10px 13px;
  border-radius: var(--radius-sm);
  font-size: .935rem;
  font-weight: 600;
  color: var(--ink-2);
  transition: background .18s, color .18s;
}
.nav a:hover { background: var(--brand-50); color: var(--brand-700); }
.nav a[aria-current="page"] { color: var(--brand-700); }
.nav a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 13px; right: 13px; bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--brand-500);
}

.header-actions { display: flex; align-items: center; gap: 10px; margin-left: 8px; }
.header-phone {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  color: var(--ink);
  font-size: .93rem;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
}
.header-phone:hover { background: var(--bg-soft); color: var(--brand-700); }
.header-phone svg { width: 17px; height: 17px; color: var(--brand-600); }

.nav-toggle {
  display: none;
  width: 44px; height: 44px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
}
.nav-toggle span {
  position: relative;
  display: block;
  width: 18px; height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform .2s, background .2s;
}
.nav-toggle span::before, .nav-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px; height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform .2s, top .2s;
}
.nav-toggle span::before { top: -6px; }
.nav-toggle span::after { top: 6px; }
.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { top: 0; transform: rotate(-45deg); }

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(42px, 6vw, 84px) 0 clamp(48px, 6vw, 76px);
  background:
    radial-gradient(1100px 520px at 88% -10%, rgba(238, 0, 51, .10), transparent 62%),
    radial-gradient(760px 420px at 4% 8%, rgba(255, 183, 3, .13), transparent 60%),
    linear-gradient(180deg, #fbfdfc 0%, #ffffff 68%);
  border-bottom: 1px solid var(--line);
}
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: center;
}
.hero h1 { margin-bottom: 18px; }
.hero h1 .accent {
  color: var(--brand-600);
  background: linear-gradient(180deg, transparent 62%, rgba(255, 183, 3, .42) 62%);
  padding: 0 2px;
}
.hero p.lead { max-width: 54ch; font-size: 1.1rem; }

.hero-badges { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 22px; }
.pill {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 13px;
  border-radius: var(--radius-pill);
  background: #fff;
  border: 1px solid var(--line);
  font-size: .82rem;
  font-weight: 600;
  color: var(--ink-2);
  box-shadow: var(--shadow-sm);
}
.pill svg { width: 15px; height: 15px; color: var(--brand-600); }
.pill.solar svg { color: var(--solar-600); }

.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }

.hero-figure { position: relative; }
.hero-figure img { width: 100%; height: auto; border-radius: var(--radius-lg); }

.float-card {
  position: absolute;
  background: rgba(255, 255, 255, .95);
  backdrop-filter: blur(8px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 12px 15px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: .82rem;
  font-weight: 600;
  color: var(--ink-2);
  animation: floaty 6s ease-in-out infinite;
}
.float-card strong { display: block; font-size: .98rem; color: var(--ink); line-height: 1.2; }
.float-card small { display: block; color: var(--muted); font-weight: 500; font-size: .72rem; }
.float-card .ic {
  width: 34px; height: 34px;
  flex: none;
  border-radius: 10px;
  display: grid; place-items: center;
  background: var(--brand-100);
  color: var(--brand-700);
}
.float-card .ic svg { width: 18px; height: 18px; }
.float-card--a { left: -10px; bottom: 16%; animation-delay: 0s; }
.float-card--b { right: -6px; top: 8%; animation-delay: 1.6s; }

@keyframes floaty {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-7px); }
}

/* Dải số liệu */
.stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(32px, 4vw, 52px);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.stats > div {
  background: #fff;
  padding: 20px 18px;
  text-align: center;
}
.stats b {
  display: block;
  font-size: clamp(1.4rem, 2.4vw, 1.85rem);
  font-weight: 800;
  color: var(--brand-700);
  line-height: 1.1;
  letter-spacing: -.03em;
}
.stats span { font-size: .82rem; color: var(--muted); }

/* --------------------------------------------------------------------------
   Cards
   -------------------------------------------------------------------------- */
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: clamp(22px, 2.6vw, 30px);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.card-hover:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(18, 161, 99, .35);
}
.card h3 { margin-bottom: 10px; }
.card p:last-child { margin-bottom: 0; }

.icon-box {
  width: 52px; height: 52px;
  border-radius: 15px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  background: var(--brand-100);
  color: var(--brand-700);
}
.icon-box svg { width: 26px; height: 26px; }
.icon-box.solar { background: var(--solar-soft); color: var(--solar-600); }
.icon-box.dark { background: rgba(255, 255, 255, .08); color: var(--brand-400); }

/* Hai khối dịch vụ lớn */
.service-split { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.service-tile {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  min-height: 330px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 28px;
  color: #fff;
  isolation: isolate;
  transition: transform .25s ease, box-shadow .25s ease;
}
.service-tile:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); color: #fff; }
.service-tile::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(180deg, rgba(6, 40, 26, .12) 0%, rgba(5, 30, 20, .88) 72%);
}
.service-tile img {
  position: absolute;
  inset: 0;
  z-index: -2;
  width: 100%; height: 100%;
  object-fit: cover;
}
.service-tile h3 { color: #fff; font-size: 1.45rem; margin-bottom: 8px; }
.service-tile p { color: rgba(255, 255, 255, .84); margin-bottom: 16px; font-size: .95rem; }
.service-tile .tag {
  align-self: flex-start;
  margin-bottom: 12px;
  padding: 5px 11px;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, .16);
  border: 1px solid rgba(255, 255, 255, .26);
  font-size: .73rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
}
.service-tile .link-arrow { color: #fff; }
.service-tile .link-arrow:hover { color: var(--brand-400); }

/* Danh sách có dấu check */
.check-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 11px; }
.check-list li { position: relative; padding-left: 30px; font-size: .95rem; }
.check-list li::before {
  content: "";
  position: absolute;
  left: 0; top: .32em;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: var(--brand-100) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23ee0033' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E") center / 12px no-repeat;
}
.section-dark .check-list li::before { background-color: rgba(255, 107, 131, .18); }

/* --------------------------------------------------------------------------
   Quy trình
   -------------------------------------------------------------------------- */
.steps { counter-reset: step; display: grid; gap: 20px; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.step { position: relative; padding-top: 8px; }
.step::before {
  counter-increment: step;
  content: "0" counter(step);
  display: block;
  font-size: .82rem;
  font-weight: 800;
  letter-spacing: .1em;
  color: var(--brand-700);
  margin-bottom: 10px;
}
.step h3 { font-size: 1.05rem; margin-bottom: 8px; }
.step p { font-size: .9rem; color: var(--muted); margin: 0; }
.step::after {
  content: "";
  position: absolute;
  top: 18px; left: 0;
  width: 34px; height: 2px;
  background: var(--brand-400);
  border-radius: 2px;
}

/* --------------------------------------------------------------------------
   Dự án
   -------------------------------------------------------------------------- */
.filters { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 28px; }
.filter-btn {
  padding: 9px 16px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-strong);
  background: #fff;
  font-size: .875rem;
  font-weight: 600;
  color: var(--ink-2);
  transition: all .18s;
}
.filter-btn:hover { border-color: var(--brand-500); color: var(--brand-700); }
.filter-btn.is-active {
  background: var(--brand-700);
  border-color: var(--brand-700);
  color: #fff;
}

.project-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.project-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #fff;
  transition: transform .22s, box-shadow .22s;
}
.project-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.project-card .thumb { position: relative; aspect-ratio: 4 / 3; overflow: hidden; background: var(--bg-soft); }
.project-card .thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s ease; }
.project-card:hover .thumb img { transform: scale(1.04); }
.project-card .thumb .badge {
  position: absolute;
  left: 12px; top: 12px;
  padding: 5px 11px;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, .94);
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--brand-700);
  box-shadow: var(--shadow-sm);
}
.project-card .body { padding: 18px 20px 20px; }
.project-card h3 { font-size: 1.05rem; margin-bottom: 6px; }
.project-card .meta { display: flex; flex-wrap: wrap; gap: 6px 14px; font-size: .82rem; color: var(--muted); }
.project-card .meta span { display: inline-flex; align-items: center; gap: 5px; }
.project-card .meta svg { width: 14px; height: 14px; }
.project-card .result {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: .88rem;
  color: var(--brand-700);
  font-weight: 650;
}

/* --------------------------------------------------------------------------
   Bảng giá
   -------------------------------------------------------------------------- */
.price-card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: transform .22s, box-shadow .22s, border-color .22s;
}
.price-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.price-card.is-featured { border-color: var(--brand-500); box-shadow: 0 18px 50px rgba(238, 0, 51, .12); }
.price-card .ribbon {
  position: absolute;
  top: -12px; left: 24px;
  background: var(--brand-600);
  color: #fff;
  font-size: .7rem;
  font-weight: 800;
  letter-spacing: .1em;
  text-transform: uppercase;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
}
.price-card h3 { font-size: 1.1rem; margin-bottom: 4px; }
.price-card .sub { font-size: .86rem; color: var(--muted); margin-bottom: 18px; }
.price-card .price {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -.03em;
  line-height: 1.1;
}
.price-card .price small { font-size: .8rem; font-weight: 600; color: var(--muted); letter-spacing: 0; }
.price-card .price-note { font-size: .8rem; color: var(--muted); margin: 6px 0 20px; }
.price-card .check-list { margin-bottom: 24px; }
.price-card .btn { margin-top: auto; }

/* --------------------------------------------------------------------------
   Testimonial
   -------------------------------------------------------------------------- */
.quote-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.quote-card .stars { color: var(--solar); letter-spacing: 2px; font-size: .95rem; }
.quote-card blockquote { margin: 0; font-size: .97rem; color: var(--ink-2); }
.quote-card blockquote::before { content: "“"; font-size: 2.2rem; line-height: 0; color: var(--brand-400); vertical-align: -.35em; margin-right: 2px; }
.quote-card .who { display: flex; align-items: center; gap: 11px; margin-top: auto; }
.avatar {
  width: 40px; height: 40px;
  border-radius: 50%;
  display: grid; place-items: center;
  background: var(--brand-100);
  color: var(--brand-700);
  font-weight: 800;
  font-size: .9rem;
}
.quote-card .who b { display: block; font-size: .9rem; color: var(--ink); line-height: 1.25; }
.quote-card .who span { font-size: .78rem; color: var(--muted); }

/* --------------------------------------------------------------------------
   FAQ
   -------------------------------------------------------------------------- */
.faq { display: grid; gap: 12px; }
.faq details {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  padding: 0 20px;
  transition: border-color .2s, box-shadow .2s;
}
.faq details[open] { border-color: rgba(238, 0, 51, .35); box-shadow: var(--shadow-sm); }
.faq summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 17px 0;
  font-weight: 650;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  width: 10px; height: 10px;
  flex: none;
  border-right: 2px solid var(--brand-600);
  border-bottom: 2px solid var(--brand-600);
  transform: rotate(45deg);
  transition: transform .22s;
  margin-top: -4px;
}
.faq details[open] summary::after { transform: rotate(-135deg); margin-top: 4px; }
.faq .answer { padding: 0 0 18px; color: var(--muted); font-size: .95rem; }
.faq .answer p:last-child { margin-bottom: 0; }

/* --------------------------------------------------------------------------
   CTA band
   -------------------------------------------------------------------------- */
.cta-band {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background:
    radial-gradient(700px 320px at 88% 0%, rgba(238, 0, 51, .30), transparent 60%),
    linear-gradient(120deg, var(--brand-800), var(--brand-600));
  color: #fff;
  padding: clamp(30px, 4.4vw, 54px);
  display: grid;
  grid-template-columns: 1.4fr .6fr;
  gap: 26px;
  align-items: center;
}
.cta-band h2 { color: #fff; margin-bottom: 10px; }
.cta-band p { color: rgba(255, 255, 255, .84); margin-bottom: 0; max-width: 46ch; }
.cta-band .actions { display: flex; gap: 12px; justify-content: flex-end; flex-wrap: wrap; }

/* --------------------------------------------------------------------------
   Máy tính chi phí
   -------------------------------------------------------------------------- */
.calc {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, .9fr);
  gap: 26px;
  align-items: start;
}
.panel {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: clamp(22px, 2.6vw, 30px);
  box-shadow: var(--shadow-sm);
}
.panel-title { display: flex; align-items: center; gap: 10px; margin-bottom: 22px; }
.panel-title .ic {
  width: 36px; height: 36px;
  border-radius: 10px;
  display: grid; place-items: center;
  background: var(--brand-100);
  color: var(--brand-700);
}
.panel-title .ic svg { width: 19px; height: 19px; }
.panel-title h3 { margin: 0; font-size: 1.05rem; }

.field { margin-bottom: 18px; }
.field > label {
  display: block;
  font-size: .875rem;
  font-weight: 650;
  color: var(--ink);
  margin-bottom: 7px;
}
.field .hint { display: block; font-size: .78rem; color: var(--muted); font-weight: 400; margin-top: 5px; }

.input, .select, .textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: #fff;
  font-size: .95rem;
  transition: border-color .16s, box-shadow .16s;
}
.input:focus, .select:focus, .textarea:focus {
  outline: none;
  border-color: var(--brand-500);
  box-shadow: var(--ring);
}
.textarea { min-height: 120px; resize: vertical; }
.select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%236f6469' stroke-width='2.4' stroke-linecap='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 17px;
  padding-right: 38px;
}

.range-row { display: flex; align-items: center; gap: 14px; }
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 6px;
  background: var(--line);
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--brand-600);
  border: 3px solid #fff;
  box-shadow: 0 2px 8px rgba(13, 122, 76, .45);
  cursor: grab;
}
input[type="range"]::-moz-range-thumb {
  width: 18px; height: 18px;
  border-radius: 50%;
  background: var(--brand-600);
  border: 3px solid #fff;
  box-shadow: 0 2px 8px rgba(13, 122, 76, .45);
  cursor: grab;
}
.range-value {
  min-width: 92px;
  text-align: right;
  font-weight: 800;
  color: var(--brand-700);
  font-size: 1rem;
  font-variant-numeric: tabular-nums;
}

.result-panel {
  background: linear-gradient(160deg, var(--brand-800), var(--brand-700) 60%, #8a0019);
  color: #fff;
  border: 0;
  position: sticky;
  top: calc(var(--header-h) + 20px);
}
.result-panel h3 { color: #fff; }
.result-panel .total-label { font-size: .82rem; letter-spacing: .1em; text-transform: uppercase; color: rgba(255, 255, 255, .62); font-weight: 700; }
.result-panel .total {
  font-size: clamp(1.9rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -.03em;
  line-height: 1.1;
  margin: 4px 0 4px;
  font-variant-numeric: tabular-nums;
}
.result-panel .total-note { font-size: .82rem; color: rgba(255, 255, 255, .62); }
.result-rows { display: grid; gap: 1px; background: rgba(255, 255, 255, .14); border-radius: var(--radius); overflow: hidden; margin: 22px 0; }
.result-rows div {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  background: rgba(255, 255, 255, .06);
  padding: 13px 16px;
  font-size: .9rem;
}
.result-rows span { color: rgba(255, 255, 255, .72); }
.result-rows b { font-variant-numeric: tabular-nums; }
.result-panel .disclaimer { font-size: .76rem; color: rgba(255, 255, 255, .55); margin: 14px 0 0; line-height: 1.5; }
.result-panel .btn { margin-top: 20px; }

/* --------------------------------------------------------------------------
   Forms
   -------------------------------------------------------------------------- */
.consent {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: .88rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--ink-2);
  cursor: pointer;
}
.consent input[type="checkbox"] {
  width: 18px;
  height: 18px;
  margin: 2px 0 0;
  flex: none;
  accent-color: var(--brand-600);
  cursor: pointer;
}
.form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 18px; }
.form-grid .full { grid-column: 1 / -1; }
.form-note { font-size: .78rem; color: var(--muted); margin-top: 14px; }
.form-status {
  display: none;
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  font-size: .9rem;
  font-weight: 600;
  background: var(--brand-100);
  color: var(--brand-800);
  border: 1px solid rgba(238, 0, 51, .26);
}
.form-status.is-error { background: #fff1f0; color: #9b1c1c; border-color: #f3c2bf; }
.form-status.is-visible { display: block; }
.field-error { display: block; font-size: .78rem; color: #b42318; margin-top: 5px; min-height: 0; }
.input.is-invalid, .select.is-invalid, .textarea.is-invalid { border-color: #d92d20; }

/* --------------------------------------------------------------------------
   Contact info list
   -------------------------------------------------------------------------- */
.info-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 16px; }
.info-list li { display: flex; gap: 13px; }
.info-list .ic {
  width: 40px; height: 40px;
  flex: none;
  border-radius: 11px;
  display: grid; place-items: center;
  background: var(--brand-100);
  color: var(--brand-700);
}
.info-list .ic svg { width: 19px; height: 19px; }
.info-list b { display: block; font-size: .78rem; text-transform: uppercase; letter-spacing: .09em; color: var(--muted); font-weight: 700; margin-bottom: 2px; }
.info-list a, .info-list span { color: var(--ink); font-weight: 600; font-size: .96rem; }

.map-frame {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  aspect-ratio: 16 / 10;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 24px;
  color: var(--muted);
  font-size: .9rem;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer { background: var(--bg-dark); color: #a89da2; font-size: .9rem; padding: 64px 0 0; }
.site-footer h4 { color: #fff; font-size: .82rem; letter-spacing: .12em; text-transform: uppercase; margin-bottom: 16px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.2fr; gap: 34px; }
.site-footer a { color: #a89da2; }
.site-footer a:hover { color: var(--brand-400); }
.site-footer .brand-text strong { color: #fff; }
.site-footer .brand-text small { color: #8b8085; }
.footer-links { list-style: none; padding: 0; margin: 0; display: grid; gap: 9px; }
.footer-desc { max-width: 34ch; margin-top: 16px; line-height: 1.6; }
.footer-contact { list-style: none; padding: 0; margin: 0; display: grid; gap: 11px; }
.footer-contact li { display: flex; gap: 9px; }
.footer-contact svg { width: 16px; height: 16px; flex: none; margin-top: 3px; color: var(--brand-400); }
.footer-bottom {
  margin-top: 48px;
  border-top: 1px solid rgba(255, 255, 255, .1);
  padding: 20px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  font-size: .8rem;
  color: #7c7176;
}

/* --------------------------------------------------------------------------
   Page header (trang con)
   -------------------------------------------------------------------------- */
.page-head {
  padding: clamp(30px, 4vw, 52px) 0 clamp(28px, 3.4vw, 44px);
  background:
    radial-gradient(800px 320px at 90% -20%, rgba(238, 0, 51, .10), transparent 60%),
    var(--bg-soft);
  border-bottom: 1px solid var(--line);
}
.page-head h1 { font-size: clamp(1.8rem, 3.4vw, 2.7rem); margin-bottom: 12px; }
.page-head p { color: var(--muted); max-width: 62ch; margin: 0; }

.breadcrumb { display: flex; flex-wrap: wrap; gap: 8px; font-size: .82rem; color: var(--muted); margin-bottom: 14px; }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--brand-700); }
.breadcrumb span { color: var(--ink-2); font-weight: 600; }
.breadcrumb .sep { color: var(--line-strong); }

/* Nội dung bài viết dài */
.prose { max-width: 74ch; }
.prose h2 { margin-top: 40px; }
.prose h3 { margin-top: 28px; }
.prose ul, .prose ol { color: var(--ink-2); }
.prose li { margin-bottom: 7px; }

/* Split content */
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(26px, 4vw, 56px); align-items: center; }
.split-media { border-radius: var(--radius-lg); overflow: hidden; border: 1px solid var(--line); background: var(--bg-soft); }
.split-media img { width: 100%; height: 100%; object-fit: cover; }

/* Table */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
table { width: 100%; border-collapse: collapse; font-size: .92rem; min-width: 520px; }
th, td { padding: 13px 16px; text-align: left; border-bottom: 1px solid var(--line); }
th { background: var(--bg-soft); font-weight: 700; color: var(--ink); font-size: .84rem; text-transform: uppercase; letter-spacing: .05em; }
tbody tr:last-child td { border-bottom: 0; }
tbody tr:hover { background: var(--brand-50); }
td.num { font-variant-numeric: tabular-nums; white-space: nowrap; }

/* Callout */
.callout {
  display: flex;
  gap: 14px;
  padding: 16px 18px;
  border-radius: var(--radius);
  background: var(--solar-soft);
  border: 1px solid rgba(224, 159, 0, .3);
  font-size: .92rem;
  color: #5a4400;
  margin: 24px 0;
}
.callout svg { width: 20px; height: 20px; flex: none; margin-top: 2px; color: var(--solar-600); }
.callout p:last-child { margin-bottom: 0; }

/* --------------------------------------------------------------------------
   Reveal animation
   -------------------------------------------------------------------------- */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .6s cubic-bezier(.22, 1, .36, 1), transform .6s cubic-bezier(.22, 1, .36, 1);
  will-change: opacity, transform;
}
html.js [data-reveal].is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  html.js [data-reveal] { opacity: 1; transform: none; }
}

/* Nút lên đầu trang */
.to-top {
  position: fixed;
  right: 20px; bottom: 20px;
  width: 46px; height: 46px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--brand-700);
  display: grid;
  place-items: center;
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all .25s;
  z-index: 90;
}
.to-top.is-visible { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--brand-700); color: #fff; border-color: var(--brand-700); }
.to-top svg { width: 20px; height: 20px; }

/* Nút gọi nhanh trên mobile */
.mobile-call {
  display: none;
  position: fixed;
  left: 16px; right: 16px; bottom: 16px;
  z-index: 95;
  box-shadow: 0 12px 30px rgba(13, 122, 76, .35);
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .nav { display: none; }
  .header-actions { margin-left: auto; }
  .navbar { display: none; }
  .nav-toggle { display: inline-flex; }

  .nav.is-open {
    display: flex;
    position: absolute;
    left: 0; right: 0;
    top: var(--header-h);
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 14px 22px 22px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-lg);
  }
  .nav.is-open a { padding: 13px 12px; font-size: 1rem; }
  .nav.is-open a[aria-current="page"]::after { display: none; }
  .nav.is-open a[aria-current="page"] { background: var(--brand-50); }

  .header-inner { position: relative; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-figure { order: -1; max-width: 560px; }
  .float-card--a { left: 4px; bottom: 8%; }
  .float-card--b { right: 4px; top: 0; }
  .grid-4, .steps, .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .project-grid, .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
  .cta-band { grid-template-columns: 1fr; }
  .cta-band .actions { justify-content: flex-start; }
  .calc { grid-template-columns: 1fr; }
  .result-panel { position: static; }
  .split { grid-template-columns: 1fr; }
  .split.rev .split-media { order: -1; }
}

@media (max-width: 720px) {
  body { font-size: 16px; }
  .brand-text strong { font-size: .88rem; letter-spacing: .02em; }
  img.brand-mark { height: 26px; }
  .brand-text small { display: none; }
  .header-phone span { display: none; }
  .header-phone { padding: 8px; }
  .header-actions .btn-primary { display: none; }
  .mobile-call { display: inline-flex; }
  .to-top { bottom: 84px; }
  .site-footer { padding-bottom: 72px; }

  .grid-2, .grid-3, .grid-4, .project-grid, .service-split, .steps, .form-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .float-card { font-size: .74rem; padding: 9px 12px; }
  .float-card .ic { width: 28px; height: 28px; }
  .hero-cta .btn { flex: 1 1 100%; }
  .section { padding: 48px 0; }
  .service-tile { min-height: 260px; }
  .footer-bottom { flex-direction: column; }
}

/* --------------------------------------------------------------------------
   In ấn
   -------------------------------------------------------------------------- */
@media print {
  .site-header, .to-top, .mobile-call, .site-footer .footer-links, .cta-band { display: none !important; }
  body { color: #000; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: .8em; }
}

/* --------------------------------------------------------------------------
   Tabs (máy tính chi phí)
   -------------------------------------------------------------------------- */
.tabs {
  display: inline-flex;
  gap: 4px;
  padding: 5px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-sm);
  margin-bottom: 26px;
}
.tab {
  border: 0;
  background: transparent;
  padding: 10px 20px;
  border-radius: var(--radius-pill);
  font-size: .93rem;
  font-weight: 650;
  color: var(--muted);
  transition: background .18s, color .18s;
}
.tab:hover { color: var(--brand-700); background: var(--brand-50); }
.tab.is-active { background: var(--brand-700); color: #fff; }
.tab.is-active:hover { background: var(--brand-700); color: #fff; }

.calc-note {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: .82rem;
  color: var(--muted);
  margin-top: 16px;
  line-height: 1.55;
}
.calc-note svg { width: 16px; height: 16px; flex: none; margin-top: 2px; color: var(--brand-600); }

.result-rows div.is-highlight { background: rgba(255, 255, 255, .14); }

@media (max-width: 720px) {
  .tabs { width: 100%; }
  .tab { flex: 1; padding: 10px 12px; }
}