/* ============================================================
   IANT — Website Marketing
   Design: "Editorial ledger" — điềm tĩnh, chính xác, thủ công.
   Serif hiển thị (Fraunces) + Inter thân bài; giấy kem + mực xanh
   sâu + đất nung. Motif: đường kẻ mảnh, số thứ tự lớn, mock bảng
   dữ liệu như một cuốn sổ cái được thiết kế lại cho phần mềm.
   ============================================================ */

/* ---------- 1. Tokens ---------- */
:root {
  --ink: #0F1E33;
  --ink-2: #14263F;
  --ink-3: #1E3350;
  --paper: #F7F2E8;
  --paper-2: #EFE7D6;
  --paper-3: #E7DCC5;
  --white: #FEFCF8;
  --accent: #C0561E;
  --accent-2: #E3A167;
  --accent-soft: #F2D9B8;
  --line: #DCD3BE;
  --line-strong: #B9AE94;
  --muted: #6E6858;
  --muted-2: #4A4638;
  --success: #2F7A4D;
  --danger: #B4432B;

  --font-display: 'Fraunces', 'Playfair Display', Georgia, 'Times New Roman', serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  --step-0: 0.875rem;   /* 14 */
  --step-1: 1rem;       /* 16 */
  --step-2: 1.125rem;   /* 18 */
  --step-3: clamp(1.25rem, 1.15rem + 0.4vw, 1.5rem);      /* 20-24 */
  --step-4: clamp(1.5rem, 1.3rem + 0.8vw, 2rem);          /* 24-32 */
  --step-5: clamp(1.875rem, 1.55rem + 1.4vw, 2.75rem);    /* 30-44 */
  --step-6: clamp(2.25rem, 1.8rem + 2.4vw, 3.5rem);       /* 36-56 */
  --step-7: clamp(2.75rem, 2.1rem + 3.6vw, 4.75rem);      /* 44-76 */

  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 48px;
  --sp-8: 64px;
  --sp-9: 96px;
  --sp-10: 128px;

  --rad-sm: 3px;
  --rad-md: 6px;
  --rad-lg: 10px;

  --shadow-sm: 0 1px 2px rgba(15, 30, 51, 0.06);
  --shadow-md: 0 8px 24px -12px rgba(15, 30, 51, 0.18);
  --shadow-lg: 0 24px 60px -24px rgba(15, 30, 51, 0.28);

  --dur: 220ms;
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);

  --container: 1240px;
  --gutter: clamp(20px, 4vw, 48px);
}

/* ---------- 2. Reset & Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-rendering: optimizeLegibility; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--step-1);
  line-height: 1.65;
  color: var(--ink);
  background: var(--paper);
  font-feature-settings: "ss01","cv11";
}
img, svg { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; transition: color var(--dur) var(--ease); }
button { font: inherit; cursor: pointer; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }
::selection { background: var(--accent); color: var(--white); }

h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 0;
  font-variation-settings: "opsz" 40, "SOFT" 30;
}
h1 { font-size: var(--step-7); letter-spacing: -0.03em; }
h2 { font-size: var(--step-6); letter-spacing: -0.025em; }
h3 { font-size: var(--step-4); letter-spacing: -0.015em; }
h4 { font-size: var(--step-3); letter-spacing: -0.01em; font-weight: 600; }
p { margin: 0 0 1em; }

/* Skip link */
.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--white); padding: 12px 16px;
  z-index: 100; font-weight: 600; font-size: 14px;
}
.skip-link:focus { left: 12px; top: 12px; }

/* ---------- 3. Layout primitives ---------- */
.container { max-width: var(--container); margin: 0 auto; padding-left: var(--gutter); padding-right: var(--gutter); }
.container-narrow { max-width: 780px; margin: 0 auto; padding-left: var(--gutter); padding-right: var(--gutter); }
.section { padding: clamp(64px, 9vw, 120px) 0; }
.section--tight { padding: clamp(48px, 6vw, 80px) 0; }
.section--dark { background: var(--ink); color: var(--paper); }
.section--dark h1, .section--dark h2, .section--dark h3, .section--dark h4 { color: var(--white); }
.section--paper2 { background: var(--paper-2); }
.section--white { background: var(--white); }

.grid { display: grid; gap: var(--sp-6); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* ---------- 4. Section header ---------- */
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: var(--sp-4);
}
.eyebrow::before {
  content: ""; display: inline-block;
  width: 28px; height: 1px; background: var(--accent);
}
.section--dark .eyebrow { color: var(--accent-2); }
.section--dark .eyebrow::before { background: var(--accent-2); }

.section-head { max-width: 720px; margin-bottom: var(--sp-8); }
.section-head p.lead { color: var(--muted-2); font-size: var(--step-2); line-height: 1.6; max-width: 60ch; }
.section--dark .section-head p.lead { color: rgba(247, 242, 232, 0.78); }

.rule {
  height: 1px; background: var(--line); border: 0; margin: 0;
}
.section--dark .rule { background: rgba(247, 242, 232, 0.14); }

/* ---------- 5. Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 40;
  background: rgba(247, 242, 232, 0.86);
  backdrop-filter: saturate(150%) blur(12px);
  -webkit-backdrop-filter: saturate(150%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.site-header.is-scrolled { border-bottom-color: var(--line); background: rgba(247, 242, 232, 0.95); }
.site-header__inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--sp-6); padding: 18px 0;
}
.brand {
  display: inline-flex; align-items: baseline; gap: 6px;
  font-family: var(--font-display); font-weight: 600; font-size: 22px;
  letter-spacing: -0.02em; color: var(--ink);
}
.brand .mark {
  display: inline-block; width: 10px; height: 10px; margin-right: 4px;
  background: var(--accent); transform: translateY(-2px);
}
.brand .dot { color: var(--accent); }

.nav { display: flex; align-items: center; gap: 4px; }
.nav a {
  padding: 10px 14px;
  font-size: 15px; font-weight: 500; color: var(--muted-2);
  border-radius: var(--rad-sm);
  position: relative;
}
.nav a:hover { color: var(--ink); }
.nav a.is-active { color: var(--ink); }
.nav a.is-active::after {
  content: ""; position: absolute; left: 14px; right: 14px; bottom: 4px;
  height: 2px; background: var(--accent);
}

.header-actions { display: flex; align-items: center; gap: var(--sp-3); }

.nav-toggle {
  display: none;
  width: 44px; height: 44px; padding: 0;
  background: transparent; border: 1px solid var(--line);
  border-radius: var(--rad-sm);
  align-items: center; justify-content: center;
  color: var(--ink);
}
.nav-toggle svg { width: 22px; height: 22px; }

@media (max-width: 960px) {
  .nav, .header-actions .btn { display: none; }
  .nav-toggle { display: inline-flex; }
}

/* Mobile menu */
.mobile-menu {
  position: fixed; inset: 0; z-index: 60;
  background: var(--paper);
  transform: translateY(-100%); transition: transform 320ms var(--ease);
  padding: 24px var(--gutter);
  overflow-y: auto;
}
.mobile-menu[data-open="true"] { transform: translateY(0); }
.mobile-menu__top { display: flex; align-items: center; justify-content: space-between; padding: 6px 0 32px; border-bottom: 1px solid var(--line); }
.mobile-menu__list { list-style: none; padding: 0; margin: 24px 0 32px; }
.mobile-menu__list a {
  display: block; padding: 14px 0;
  font-family: var(--font-display); font-size: 28px;
  color: var(--ink); border-bottom: 1px solid var(--line);
}
.mobile-menu__list a:hover { color: var(--accent); }
body.is-locked { overflow: hidden; }

/* ---------- 6. Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  padding: 14px 22px;
  font-family: var(--font-body); font-size: 15px; font-weight: 600;
  letter-spacing: 0.005em;
  border-radius: var(--rad-sm);
  border: 1px solid transparent;
  min-height: 46px;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  white-space: nowrap;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn svg { width: 16px; height: 16px; }

.btn--primary { background: var(--accent); color: var(--white); }
.btn--primary:hover { background: #A94818; box-shadow: 0 8px 18px -8px rgba(192, 86, 30, 0.6); }

.btn--ink { background: var(--ink); color: var(--white); }
.btn--ink:hover { background: var(--ink-2); box-shadow: 0 8px 18px -8px rgba(15, 30, 51, 0.4); }

.btn--ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.btn--ghost:hover { border-color: var(--ink); background: rgba(15, 30, 51, 0.04); }

.section--dark .btn--ghost { color: var(--white); border-color: rgba(247, 242, 232, 0.32); }
.section--dark .btn--ghost:hover { border-color: var(--white); background: rgba(255,255,255,0.06); }

.btn-arrow { display: inline-flex; align-items: center; gap: 8px; font-weight: 600; color: var(--ink); border-bottom: 1px solid transparent; padding-bottom: 2px; }
.btn-arrow:hover { color: var(--accent); border-bottom-color: var(--accent); }
.btn-arrow svg { width: 14px; height: 14px; transition: transform var(--dur) var(--ease); }
.btn-arrow:hover svg { transform: translateX(3px); }
.section--dark .btn-arrow { color: var(--white); }
.section--dark .btn-arrow:hover { color: var(--accent-2); border-bottom-color: var(--accent-2); }

/* ---------- 7. Hero ---------- */
.hero {
  position: relative;
  padding: clamp(56px, 8vw, 96px) 0 clamp(64px, 9vw, 120px);
  overflow: hidden;
}
.hero__layout {
  display: grid; grid-template-columns: 1.05fr 1fr;
  gap: clamp(32px, 5vw, 72px);
  align-items: center;
}
@media (max-width: 1000px) {
  .hero__layout { grid-template-columns: 1fr; }
}
.hero__meta {
  display: flex; align-items: center; gap: 14px;
  font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: var(--sp-5);
}
.hero__meta .dash { width: 24px; height: 1px; background: var(--line-strong); }
.hero__meta .no { color: var(--accent); font-weight: 700; }

.hero h1 {
  font-size: var(--step-7);
  line-height: 1.02;
  letter-spacing: -0.035em;
  margin-bottom: var(--sp-5);
  max-width: 14ch;
}
.hero h1 em {
  font-style: italic; font-family: var(--font-display); font-weight: 400;
  color: var(--accent);
  font-variation-settings: "opsz" 144, "SOFT" 100;
}
.hero__lead {
  font-size: var(--step-3); line-height: 1.55;
  color: var(--muted-2); max-width: 52ch;
  margin-bottom: var(--sp-7);
}
.hero__cta { display: flex; flex-wrap: wrap; gap: var(--sp-3); }
.hero__trust {
  margin-top: var(--sp-7);
  display: grid; grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line); padding-top: var(--sp-5);
  gap: var(--sp-5);
}
.hero__trust dt {
  font-family: var(--font-display); font-size: clamp(28px, 3vw, 36px);
  letter-spacing: -0.02em; color: var(--ink); font-weight: 500;
  line-height: 1;
}
.hero__trust dd {
  margin: 6px 0 0; font-size: 13px; color: var(--muted);
  line-height: 1.4;
}
@media (max-width: 560px) {
  .hero__trust { grid-template-columns: 1fr; gap: var(--sp-4); }
}

/* ---------- 8. Product mockup (HTML/CSS) ---------- */
.mock {
  position: relative;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-lg);
  border-radius: var(--rad-md);
  overflow: hidden;
}
.mock__bar {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 16px;
  background: linear-gradient(180deg, var(--paper-2), var(--paper));
  border-bottom: 1px solid var(--line);
}
.mock__dot { width: 10px; height: 10px; border-radius: 50%; background: var(--line-strong); }
.mock__dot:nth-child(1) { background: #E48D77; }
.mock__dot:nth-child(2) { background: #E9C46A; }
.mock__dot:nth-child(3) { background: #8AB58C; }
.mock__url {
  margin-left: 10px; padding: 4px 12px; border-radius: 10px;
  background: var(--white); border: 1px solid var(--line);
  font-family: var(--font-mono); font-size: 11px; color: var(--muted);
  flex: 1;
}

.mock__body { display: grid; grid-template-columns: 180px 1fr; min-height: 420px; }
.mock__side {
  background: var(--paper-2); border-right: 1px solid var(--line);
  padding: 16px 12px;
}
.mock__side-title {
  font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--muted); padding: 4px 8px; margin-bottom: 8px;
}
.mock__side-item {
  display: flex; align-items: center; gap: 10px;
  padding: 8px 10px; border-radius: 4px;
  font-size: 13px; color: var(--ink-2); margin-bottom: 2px;
}
.mock__side-item.is-active { background: var(--ink); color: var(--white); }
.mock__side-item .ico { width: 14px; height: 14px; opacity: 0.7; }
.mock__side-item.is-active .ico { opacity: 1; }

.mock__main { padding: 20px 22px; background: var(--white); display: grid; gap: 16px; align-content: start; }
.mock__crumb { display: flex; align-items: center; gap: 8px; font-size: 11px; color: var(--muted); font-family: var(--font-mono); letter-spacing: 0.08em; text-transform: uppercase; }
.mock__crumb .sep { opacity: 0.5; }
.mock__h { font-family: var(--font-display); font-size: 20px; color: var(--ink); font-weight: 500; letter-spacing: -0.01em; }

.mock__kpi { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.mock__kpi > div {
  padding: 10px 12px; border: 1px solid var(--line); border-radius: 4px;
  background: var(--paper);
}
.mock__kpi label { display: block; font-size: 10px; color: var(--muted); font-family: var(--font-mono); text-transform: uppercase; letter-spacing: 0.1em; }
.mock__kpi strong { display: block; font-family: var(--font-display); font-size: 20px; color: var(--ink); font-weight: 500; margin-top: 2px; letter-spacing: -0.01em; }
.mock__kpi span { font-size: 10px; color: var(--success); font-weight: 600; margin-left: 4px; }
.mock__kpi span.down { color: var(--danger); }

.mock__chart {
  height: 90px; border: 1px solid var(--line); border-radius: 4px;
  padding: 12px; background: var(--paper);
  display: flex; align-items: flex-end; gap: 6px;
}
.mock__chart span {
  flex: 1; background: var(--ink); border-radius: 2px 2px 0 0;
  opacity: 0.85;
}
.mock__chart span:nth-child(3n) { background: var(--accent); opacity: 1; }

.mock__table { border: 1px solid var(--line); border-radius: 4px; overflow: hidden; }
.mock__table > div {
  display: grid; grid-template-columns: 1.4fr 1fr 0.9fr 0.8fr;
  padding: 8px 12px; font-size: 12px; align-items: center;
  border-top: 1px solid var(--line);
}
.mock__table > div:first-child { border-top: 0; background: var(--paper-2); font-family: var(--font-mono); font-size: 10px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--muted); }
.mock__table .status {
  justify-self: start; padding: 2px 8px; font-size: 10px; border-radius: 20px;
  background: rgba(47,122,77,0.14); color: var(--success);
  font-weight: 600;
}
.mock__table .status.pending { background: rgba(233,161,103,0.22); color: #7C4B10; }

@media (max-width: 700px) {
  .mock__body { grid-template-columns: 1fr; }
  .mock__side { display: none; }
  .mock__kpi { grid-template-columns: 1fr 1fr; }
  .mock__table > div { grid-template-columns: 1.2fr 1fr 0.8fr; }
  .mock__table .col-4 { display: none; }
}

/* ---------- 9. Cards ---------- */
.cards { display: grid; gap: var(--sp-5); }
.card {
  background: var(--white);
  border: 1px solid var(--line);
  padding: var(--sp-6);
  border-radius: var(--rad-md);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  position: relative;
}
.card:hover { border-color: var(--line-strong); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.card__num {
  font-family: var(--font-mono); font-size: 12px;
  color: var(--accent); letter-spacing: 0.14em;
  margin-bottom: var(--sp-4); display: block;
}
.card__icon {
  width: 44px; height: 44px; margin-bottom: var(--sp-4);
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--paper-2); border-radius: var(--rad-sm);
  color: var(--ink);
}
.card__icon svg { width: 22px; height: 22px; }
.card h3 { margin-bottom: var(--sp-3); }
.card p { color: var(--muted-2); margin: 0; }

/* Diff cards row */
.diff-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--sp-5); }
@media (max-width: 900px) { .diff-cards { grid-template-columns: 1fr; } }

/* Module grid */
.modules {
  display: grid; grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line-strong);
  border-left: 1px solid var(--line-strong);
}
.modules a {
  display: block; padding: var(--sp-6);
  background: var(--white);
  border-right: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
  position: relative; min-height: 168px;
}
.modules a:hover { background: var(--ink); color: var(--white); }
.modules a:hover .module__num { color: var(--accent-2); }
.modules a:hover .module__icon { color: var(--accent-2); }
.module__num { font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.14em; color: var(--muted); }
.module__icon { margin: 12px 0; color: var(--ink); }
.module__icon svg { width: 26px; height: 26px; }
.module__name { font-family: var(--font-display); font-size: 20px; letter-spacing: -0.01em; line-height: 1.2; font-weight: 500; }
.module__arrow { position: absolute; right: var(--sp-5); bottom: var(--sp-5); opacity: 0; transition: opacity var(--dur) var(--ease); }
.modules a:hover .module__arrow { opacity: 1; }

@media (max-width: 1000px) { .modules { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .modules { grid-template-columns: 1fr; } }

/* ---------- 10. Steps / Process timeline ---------- */
.steps {
  display: grid; grid-template-columns: repeat(5, 1fr);
  border-top: 1px solid var(--line-strong);
  counter-reset: step;
}
.step {
  padding: var(--sp-6) var(--sp-5);
  border-right: 1px solid var(--line);
  position: relative;
}
.step:last-child { border-right: 0; }
.step__num {
  font-family: var(--font-display); font-size: clamp(48px, 5vw, 72px);
  color: var(--accent); font-weight: 400; line-height: 0.9;
  font-variation-settings: "opsz" 144;
  display: block; margin-bottom: var(--sp-4);
  letter-spacing: -0.03em;
}
.step__num::before { content: "0"; }
.step h3 { font-size: 18px; margin-bottom: var(--sp-3); font-weight: 600; }
.step p { color: var(--muted-2); font-size: 14px; margin: 0; line-height: 1.6; }
@media (max-width: 900px) {
  .steps { grid-template-columns: 1fr; }
  .step { border-right: 0; border-bottom: 1px solid var(--line); }
  .step:last-child { border-bottom: 0; }
}

/* ---------- 11. Package cards ---------- */
.packages {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--sp-5);
}
.package {
  background: var(--white); border: 1px solid var(--line);
  padding: var(--sp-7) var(--sp-6);
  border-radius: var(--rad-md);
  display: flex; flex-direction: column;
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.package:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.package--featured {
  border-color: var(--accent); border-width: 1px;
  background: linear-gradient(180deg, var(--white) 0%, var(--paper) 100%);
  position: relative;
}
.package--featured::before {
  content: "Được chọn nhiều nhất";
  position: absolute; top: -12px; left: var(--sp-6);
  background: var(--accent); color: var(--white);
  font-family: var(--font-mono); font-size: 11px; text-transform: uppercase; letter-spacing: 0.12em;
  padding: 5px 10px; border-radius: var(--rad-sm);
  font-weight: 600;
}
.package__eyebrow {
  font-family: var(--font-mono); font-size: 11px; text-transform: uppercase;
  letter-spacing: 0.14em; color: var(--muted);
}
.package__name { font-family: var(--font-display); font-size: 30px; letter-spacing: -0.02em; margin: 10px 0 12px; font-weight: 500; }
.package__desc { color: var(--muted-2); margin-bottom: var(--sp-5); font-size: 15px; }
.package__list { list-style: none; padding: 0; margin: 0 0 var(--sp-6); border-top: 1px solid var(--line); }
.package__list li { padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 14px; color: var(--muted-2); display: flex; gap: 10px; align-items: flex-start; }
.package__list li::before {
  content: ""; flex: 0 0 6px; height: 6px; width: 6px; margin-top: 8px;
  background: var(--accent); border-radius: 50%;
}
.package a.btn { margin-top: auto; }

@media (max-width: 960px) { .packages { grid-template-columns: 1fr; } }

/* ---------- 12. CTA band ---------- */
.cta-band { background: var(--ink); color: var(--paper); padding: clamp(56px, 8vw, 96px) 0; position: relative; overflow: hidden; }
.cta-band::before {
  content: ""; position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(247,242,232,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(247,242,232,0.05) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at 80% 50%, rgba(0,0,0,0.6), transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 80% 50%, rgba(0,0,0,0.6), transparent 70%);
}
.cta-band__inner {
  position: relative;
  display: grid; grid-template-columns: 1.4fr 1fr; gap: var(--sp-7); align-items: center;
}
.cta-band h2 { color: var(--white); font-size: var(--step-6); margin-bottom: var(--sp-4); max-width: 18ch; }
.cta-band p { color: rgba(247,242,232,0.72); font-size: var(--step-2); max-width: 44ch; margin: 0; }
.cta-band__actions { display: flex; flex-wrap: wrap; gap: var(--sp-3); justify-content: flex-end; }
@media (max-width: 900px) {
  .cta-band__inner { grid-template-columns: 1fr; }
  .cta-band__actions { justify-content: flex-start; }
}

/* ---------- 13. Footer ---------- */
.site-footer {
  background: var(--ink);
  color: rgba(247,242,232,0.72);
  padding: clamp(56px, 6vw, 80px) 0 32px;
}
.site-footer .container {
  display: grid; grid-template-columns: 1.4fr 1fr 1fr;
  gap: var(--sp-7);
}
.site-footer h4 {
  font-family: var(--font-mono); font-size: 11px; text-transform: uppercase; letter-spacing: 0.14em;
  color: var(--paper-3);
  font-weight: 600; margin-bottom: var(--sp-4);
}
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { margin-bottom: 10px; }
.site-footer a { color: rgba(247,242,232,0.72); }
.site-footer a:hover { color: var(--accent-2); }
.site-footer .brand { color: var(--white); font-size: 26px; margin-bottom: var(--sp-4); }
.site-footer .brand .mark { background: var(--accent); }
.site-footer .tagline { max-width: 32ch; font-size: 14px; margin-bottom: var(--sp-4); line-height: 1.55; }
.site-footer .contact-email {
  font-family: var(--font-display); font-size: 22px; color: var(--white);
  border-bottom: 1px solid rgba(247,242,232,0.24); padding-bottom: 4px; letter-spacing: -0.01em;
}
.site-footer .legal-note {
  margin-top: var(--sp-4); font-size: 12px; line-height: 1.6;
  color: rgba(247,242,232,0.56); max-width: 32ch;
}
.site-footer__bottom {
  margin-top: var(--sp-8); padding-top: var(--sp-5);
  border-top: 1px solid rgba(247,242,232,0.14);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--sp-3);
  font-size: 13px; color: rgba(247,242,232,0.56);
}
@media (max-width: 800px) {
  .site-footer .container { grid-template-columns: 1fr; }
}

/* ---------- 14. Sub-hero (interior pages) ---------- */
.subhero {
  padding: clamp(80px, 10vw, 140px) 0 clamp(48px, 7vw, 96px);
  border-bottom: 1px solid var(--line);
}
.subhero h1 { font-size: var(--step-6); max-width: 18ch; margin-bottom: var(--sp-5); }
.subhero p.lead { font-size: var(--step-3); color: var(--muted-2); max-width: 56ch; margin: 0; }

/* ---------- 15. About page blocks ---------- */
.split {
  display: grid; grid-template-columns: 0.9fr 1.4fr;
  gap: clamp(24px, 4vw, 64px);
  align-items: start;
}
.split h2 { max-width: 12ch; }
.split .body { color: var(--muted-2); font-size: var(--step-2); line-height: 1.7; }
.split .body p { margin: 0 0 1.2em; }
@media (max-width: 800px) { .split { grid-template-columns: 1fr; } }

/* ---------- 16. Module list (Sản phẩm) ---------- */
.module-list { display: grid; gap: 0; border-top: 1px solid var(--line-strong); }
.module-row {
  display: grid; grid-template-columns: 120px 1fr 2fr;
  gap: var(--sp-6);
  padding: var(--sp-7) 0;
  border-bottom: 1px solid var(--line);
  align-items: start;
}
.module-row__num {
  font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.14em; color: var(--accent);
  padding-top: 6px;
}
.module-row__name {
  font-family: var(--font-display); font-size: var(--step-4); font-weight: 500; letter-spacing: -0.015em; color: var(--ink);
  line-height: 1.15;
}
.module-row__list { list-style: none; padding: 0; margin: 0; color: var(--muted-2); font-size: 15px; line-height: 1.6; }
.module-row__list li { padding: 6px 0 6px 22px; position: relative; }
.module-row__list li::before {
  content: ""; position: absolute; left: 0; top: 15px;
  width: 10px; height: 1px; background: var(--accent);
}
@media (max-width: 800px) {
  .module-row { grid-template-columns: 1fr; gap: var(--sp-3); padding: var(--sp-6) 0; }
}

/* ---------- 17. Form ---------- */
.form-layout {
  display: grid; grid-template-columns: 1.6fr 1fr;
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}
@media (max-width: 900px) { .form-layout { grid-template-columns: 1fr; } }

.form {
  background: var(--white); border: 1px solid var(--line);
  border-radius: var(--rad-md);
  padding: clamp(28px, 4vw, 44px);
}
.form fieldset { border: 0; padding: 0; margin: 0 0 var(--sp-5); }
.form legend { padding: 0; font-family: var(--font-mono); font-size: 11px; text-transform: uppercase; letter-spacing: 0.14em; color: var(--muted); margin-bottom: var(--sp-4); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--sp-4); }
.form-grid > .field-full { grid-column: 1 / -1; }
@media (max-width: 640px) { .form-grid { grid-template-columns: 1fr; } }

.field { display: flex; flex-direction: column; }
.field label {
  font-size: 13px; font-weight: 600; color: var(--ink);
  margin-bottom: 6px;
}
.field label .req { color: var(--accent); margin-left: 2px; }
.field input, .field select, .field textarea {
  font: inherit;
  padding: 12px 14px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--rad-sm);
  color: var(--ink);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
  min-height: 46px;
}
.field textarea { min-height: 120px; resize: vertical; line-height: 1.5; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--ink); background: var(--white);
}
.field .hint { font-size: 12px; color: var(--muted); margin-top: 6px; }
.field .err { font-size: 12px; color: var(--danger); margin-top: 6px; font-weight: 500; display: none; }
.field.is-invalid input, .field.is-invalid select, .field.is-invalid textarea { border-color: var(--danger); }
.field.is-invalid .err { display: block; }

.checkbox-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px 16px; }
@media (max-width: 560px) { .checkbox-grid { grid-template-columns: 1fr; } }
.checkbox-grid label {
  display: flex; align-items: center; gap: 10px; padding: 8px 10px;
  border: 1px solid var(--line); border-radius: var(--rad-sm);
  font-size: 14px; font-weight: 500; color: var(--muted-2);
  cursor: pointer; transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease), color var(--dur) var(--ease);
  background: var(--paper);
}
.checkbox-grid label:hover { border-color: var(--line-strong); color: var(--ink); }
.checkbox-grid input:checked + span { color: var(--ink); font-weight: 600; }
.checkbox-grid label:has(input:checked) { border-color: var(--ink); background: var(--white); }
.checkbox-grid input { accent-color: var(--accent); width: 16px; height: 16px; }

.honeypot { position: absolute !important; left: -9999px !important; height: 0; width: 0; overflow: hidden; }

.form__consent { font-size: 13px; color: var(--muted); margin: var(--sp-4) 0 var(--sp-5); line-height: 1.55; }
.form__consent a { color: var(--ink); border-bottom: 1px solid var(--line-strong); }
.form__consent a:hover { color: var(--accent); border-bottom-color: var(--accent); }

.form__status {
  padding: 14px 16px; border-radius: var(--rad-sm);
  font-size: 14px; margin-bottom: var(--sp-4);
  display: none;
}
.form__status.is-visible { display: block; }
.form__status.is-success { background: rgba(47,122,77,0.1); color: var(--success); border: 1px solid rgba(47,122,77,0.3); }
.form__status.is-error { background: rgba(180,67,43,0.08); color: var(--danger); border: 1px solid rgba(180,67,43,0.28); }

/* Contact aside */
.contact-side { padding: var(--sp-6); background: var(--paper-2); border-radius: var(--rad-md); border: 1px solid var(--line); }
.contact-side h2 { font-size: var(--step-4); margin-bottom: var(--sp-3); }
.contact-side .email {
  font-family: var(--font-display); font-size: 26px; letter-spacing: -0.01em;
  border-bottom: 1px solid var(--line-strong); padding-bottom: 4px;
  display: inline-block; margin: var(--sp-3) 0 var(--sp-4);
}
.contact-side .email:hover { color: var(--accent); border-bottom-color: var(--accent); }
.contact-side p { color: var(--muted-2); font-size: 14px; margin: 0; }
.contact-side .rule-hz { margin: var(--sp-5) 0; }
.contact-side .facts { list-style: none; padding: 0; margin: 0; }
.contact-side .facts li { display: grid; grid-template-columns: 120px 1fr; padding: 8px 0; border-bottom: 1px solid var(--line); font-size: 13px; color: var(--muted-2); }
.contact-side .facts li:last-child { border-bottom: 0; }
.contact-side .facts strong { font-family: var(--font-mono); font-size: 11px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--muted); font-weight: 600; }

/* ---------- 18. Prose (legal pages) ---------- */
.prose {
  max-width: 720px; margin: 0 auto;
  font-size: 16px; line-height: 1.75; color: var(--muted-2);
}
.prose h1 { font-size: var(--step-6); color: var(--ink); margin-bottom: var(--sp-3); }
.prose .meta { font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); margin-bottom: var(--sp-6); border-bottom: 1px solid var(--line); padding-bottom: var(--sp-4); }
.prose h2 {
  font-size: var(--step-4); color: var(--ink); margin: var(--sp-8) 0 var(--sp-4); font-weight: 600;
  font-family: var(--font-display); font-weight: 500;
  display: flex; align-items: baseline; gap: 12px;
}
.prose h2 .num { font-family: var(--font-mono); font-size: 14px; color: var(--accent); font-weight: 700; }
.prose ul { padding-left: 22px; margin: 0 0 1.4em; }
.prose li { margin-bottom: 8px; }
.prose strong { color: var(--ink); font-weight: 600; }
.prose a { color: var(--ink); border-bottom: 1px solid var(--accent); }
.prose a:hover { color: var(--accent); }
.prose .intro { font-size: 18px; color: var(--ink); }

/* ---------- 19. 404 ---------- */
.notfound {
  min-height: 70vh; display: grid; place-items: center;
  text-align: center; padding: 96px 0; position: relative; overflow: hidden;
}
.notfound__ghost {
  font-family: var(--font-display); font-size: clamp(180px, 30vw, 380px);
  color: var(--paper-3); position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%); font-weight: 500; letter-spacing: -0.05em;
  line-height: 1; z-index: 0; user-select: none;
}
.notfound__inner { position: relative; z-index: 1; max-width: 480px; }
.notfound h1 { margin-bottom: var(--sp-4); font-size: var(--step-6); }
.notfound p { color: var(--muted-2); font-size: var(--step-2); margin-bottom: var(--sp-6); }

/* ---------- 20. Reveal animation ---------- */
@keyframes iant-reveal-in {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: none; }
}
.js .reveal { animation: iant-reveal-in 700ms var(--ease) both; }
@media (prefers-reduced-motion: reduce) {
  .js .reveal { animation: none; opacity: 1; transform: none; }
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
}
@media print {
  .js .reveal { animation: none; opacity: 1; transform: none; }
}

/* ---------- 21. Utilities ---------- */
.center { text-align: center; }
.mt-0 { margin-top: 0; }
.mt-4 { margin-top: var(--sp-4); }
.mt-6 { margin-top: var(--sp-6); }
.divider { height: 1px; background: var(--line); border: 0; margin: 0; }