:root {
  --ink: #101820;
  --muted: #586b76;
  --line: #d3dde1;
  --paper: #f4f7f8;
  --white: #ffffff;
  --gold: #c9973a;
  --steel: #1f6f8b;
  --green: #2f7d67;
  --charcoal: #17242b;
  --charcoal-2: #22333b;
  --mist: #e7eef1;
  --panel: #fbfcfb;
  --sky: #dfeaf0;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

section[id] { scroll-margin-top: 112px; }

body {
  margin: 0;
  background: linear-gradient(180deg, #f4f7f8 0%, #eef3f4 46%, #f7f8f5 100%);
  color: var(--ink);
  font-family: Inter, "Avenir Next", "PingFang SC", "Noto Sans", Arial, sans-serif;
}

a { color: inherit; text-decoration: none; }

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: grid;
  grid-template-columns: minmax(286px, 1fr) auto auto;
  gap: 22px;
  align-items: center;
  padding: 10px 34px;
  background: rgba(248, 251, 250, 0.88);
  border-bottom: 1px solid rgba(16, 24, 32, 0.12);
  color: var(--ink);
  backdrop-filter: blur(20px);
}

.brand { display: inline-flex; gap: 16px; align-items: center; min-width: 0; }
.brand img {
  width: 76px;
  height: 76px;
  background: var(--white);
  border-radius: 8px;
  padding: 4px;
  box-shadow: 0 14px 34px rgba(16, 24, 32, 0.16), 0 0 0 1px rgba(201, 151, 58, 0.26);
}
.brand span { display: grid; gap: 1px; }
.brand strong { font-size: 24px; letter-spacing: 0; }
.brand small { color: var(--muted); font-size: 14px; }

.nav { display: flex; gap: 19px; color: #405460; font-size: 14px; white-space: nowrap; }
.nav a { padding: 8px 0; }
.nav a:hover { color: var(--steel); }

.language-switch {
  display: inline-flex;
  gap: 4px;
  padding: 4px;
  border: 1px solid rgba(16, 24, 32, 0.14);
  border-radius: 8px;
  background: rgba(16, 24, 32, 0.05);
}

.lang-button {
  border: 0;
  border-radius: 6px;
  padding: 8px 11px;
  background: transparent;
  color: #52636d;
  font: inherit;
  font-size: 13px;
  cursor: pointer;
}

.lang-button.active { background: var(--ink); color: var(--white); }

.hero {
  position: relative;
  min-height: 94vh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  align-items: end;
  gap: 44px;
  overflow: hidden;
  padding: 150px 56px 62px;
  background: linear-gradient(135deg, #f8faf9 0%, #e7eff2 54%, #dbe7eb 100%);
  color: var(--ink);
}

.hero-canvas,
.hero-shade {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-canvas { background: #e9f0f2; }

.hero-shade {
  background:
    linear-gradient(90deg, rgba(248, 250, 249, 0.98) 0%, rgba(244, 248, 248, 0.9) 43%, rgba(229, 238, 241, 0.48) 100%),
    linear-gradient(0deg, rgba(255, 255, 255, 0.22), rgba(255, 255, 255, 0));
}

.hero-content,
.hero-panel { position: relative; z-index: 2; }

.hero-content { max-width: 980px; display: grid; gap: 24px; }
.eyebrow,
.section-heading span,
.intro-band span,
.vietnam-section span,
.contact-section span {
  margin: 0;
  color: var(--steel);
  font-size: 13px;
  font-weight: 780;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p { margin: 0; }

h1 {
  max-width: 980px;
  font-size: clamp(42px, 6.1vw, 82px);
  line-height: 1.04;
  letter-spacing: 0;
  white-space: pre-line;
}

html[lang="vi"] h1 {
  max-width: 1120px;
  font-size: clamp(40px, 5.3vw, 72px);
  line-height: 1.08;
}

.hero-copy { max-width: 760px; color: #49616d; font-size: 20px; line-height: 1.75; }

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  max-width: 760px;
  border-top: 1px solid rgba(31, 111, 139, 0.22);
  border-bottom: 1px solid rgba(31, 111, 139, 0.22);
}

.hero-metrics div {
  min-height: 96px;
  display: grid;
  align-content: center;
  gap: 8px;
  padding: 16px 20px 16px 0;
  border-right: 1px solid rgba(31, 111, 139, 0.22);
}

.hero-metrics div:last-child { border-right: 0; }
.hero-metrics strong { font-size: 30px; color: var(--ink); }
.hero-metrics span { color: var(--muted); font-size: 13px; line-height: 1.5; }

.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  border-radius: 8px;
  padding: 0 18px;
  font-weight: 720;
}
.primary-action { background: var(--gold); color: var(--ink); }
.secondary-action { background: rgba(255, 255, 255, 0.78); border: 1px solid rgba(31, 111, 139, 0.24); color: var(--ink); }

.hero-panel {
  display: grid;
  gap: 10px;
  padding: 24px;
  border-left: 3px solid var(--gold);
  background: rgba(255, 255, 255, 0.72);
  color: var(--ink);
  backdrop-filter: blur(16px);
  box-shadow: 0 22px 60px rgba(31, 55, 65, 0.14);
}

.hero-panel span { color: var(--muted); font-size: 13px; }
.hero-panel strong { margin-bottom: 8px; font-size: 17px; line-height: 1.55; }

.proof-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  background: #edf4f6;
  color: var(--ink);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.proof-strip div {
  min-height: 128px;
  display: grid;
  align-content: center;
  gap: 10px;
  padding: 28px 42px;
  border-right: 1px solid var(--line);
}

.proof-strip div:last-child { border-right: 0; }
.proof-strip span { color: var(--steel); font-size: 12px; font-weight: 780; letter-spacing: 0.08em; }
.proof-strip strong { font-size: clamp(21px, 2.6vw, 34px); line-height: 1.15; }

.intro-band,
.section,
.contact-section,
.line-system-section,
.equipment-section {
  max-width: 1240px;
  margin: 0 auto;
  padding: 92px 30px;
}

.intro-band {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 54px;
  border-bottom: 1px solid var(--line);
}

.line-system-section {
  display: grid;
  gap: 42px;
  background: #f8faf9;
}

.line-system-heading {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 44px;
  align-items: end;
}

.line-system-heading span { color: var(--steel); font-size: 13px; font-weight: 780; letter-spacing: 0.08em; text-transform: uppercase; }
.line-system-heading h2 { margin-top: 12px; font-size: clamp(32px, 4.6vw, 56px); line-height: 1.08; }
.line-system-heading p { color: var(--muted); font-size: 17px; line-height: 1.85; }

.line-map {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-top: 1px solid #cfd8d4;
  border-left: 1px solid #cfd8d4;
}

.line-map div {
  min-height: 190px;
  display: grid;
  align-content: start;
  gap: 22px;
  padding: 24px;
  border-right: 1px solid #cfd8d4;
  border-bottom: 1px solid #cfd8d4;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.72), rgba(255, 255, 255, 0.38));
}

.line-map span { color: var(--gold); font-weight: 800; }
.line-map strong { max-width: 150px; font-size: 24px; line-height: 1.2; margin-top: 46px; }
.line-map p { color: var(--muted); font-size: 14px; line-height: 1.7; }

.equipment-section {
  display: grid;
  gap: 34px;
  max-width: none;
  background: linear-gradient(180deg, #f3f7f8 0%, #e7eff2 100%);
  color: var(--ink);
}

.equipment-heading {
  width: min(1180px, calc(100vw - 60px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 44px;
  align-items: end;
}

.equipment-heading span { color: var(--steel); font-size: 13px; font-weight: 780; letter-spacing: 0.08em; text-transform: uppercase; }
.equipment-heading h2 { margin-top: 12px; font-size: clamp(32px, 4.6vw, 56px); line-height: 1.08; }
.equipment-heading p { color: var(--muted); font-size: 17px; line-height: 1.85; }

.equipment-grid {
  width: min(1180px, calc(100vw - 60px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.equipment-grid article {
  display: grid;
  grid-template-rows: auto 1fr;
  min-height: 470px;
  overflow: hidden;
  border: 1px solid rgba(31, 111, 139, 0.16);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.76);
  box-shadow: 0 18px 46px rgba(31, 55, 65, 0.12);
}

.equipment-grid img {
  width: 100%;
  aspect-ratio: 1.35;
  object-fit: cover;
  display: block;
  background: #dfe7e3;
}

.equipment-grid article div { padding: 24px; }
.equipment-grid span { color: var(--steel); font-size: 12px; font-weight: 780; letter-spacing: 0.08em; }
.equipment-grid h3 { margin-top: 16px; font-size: 25px; line-height: 1.18; }
.equipment-grid p { margin-top: 12px; color: var(--muted); line-height: 1.75; }

.intro-band h2,
.section-heading h2,
.vietnam-section h2,
.contact-section h2 {
  margin-top: 12px;
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.14;
  letter-spacing: 0;
}

.intro-band p,
.vietnam-section p,
.contact-section p { color: var(--muted); font-size: 17px; line-height: 1.85; }

.split-section {
  display: grid;
  grid-template-columns: 0.72fr 1.28fr;
  gap: 46px;
}

.section-heading { position: sticky; top: 104px; align-self: start; }
.section-heading.compact { position: static; max-width: 760px; margin-bottom: 34px; }

.solution-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.solution-list article {
  min-height: 250px;
  padding: 32px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.84), rgba(255, 255, 255, 0.46)),
    linear-gradient(180deg, transparent 0%, rgba(31, 111, 139, 0.08) 100%);
  position: relative;
  overflow: hidden;
}

.solution-list article::after {
  content: "";
  position: absolute;
  right: 22px;
  bottom: 22px;
  width: 74px;
  height: 74px;
  border: 1px solid rgba(16, 24, 32, 0.16);
  border-radius: 50%;
  box-shadow: inset 0 0 0 18px rgba(201, 151, 58, 0.08);
}

.solution-list span { color: var(--gold); font-weight: 780; }
.solution-list h3 { margin-top: 34px; font-size: 22px; }
.solution-list p { margin-top: 12px; color: var(--muted); line-height: 1.75; }
.solution-list em {
  display: inline-flex;
  margin-top: 30px;
  color: var(--steel);
  font-style: normal;
  font-size: 12px;
  font-weight: 780;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.capability-section { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.capability-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}
.capability-grid div {
  min-height: 220px;
  padding: 28px;
  background: linear-gradient(180deg, #ffffff, #f4f8f9);
  color: var(--ink);
  border: 1px solid rgba(31, 111, 139, 0.16);
  border-radius: 8px;
  box-shadow: 0 12px 32px rgba(31, 55, 65, 0.08);
}
.capability-grid strong { font-size: 38px; color: var(--steel); }
.capability-grid p { margin-top: 32px; color: var(--muted); line-height: 1.7; }

.delivery-section { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: 44px; }
.timeline { display: grid; gap: 0; margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.timeline li { display: grid; grid-template-columns: 170px 1fr; gap: 24px; padding: 24px 0; border-bottom: 1px solid var(--line); }
.timeline strong { font-size: 18px; }
.timeline span { color: var(--muted); line-height: 1.7; }
.timeline .ai-step {
  padding: 26px 24px;
  margin: 0 0 10px;
  border: 1px solid rgba(201, 151, 58, 0.5);
  background: rgba(201, 151, 58, 0.08);
}

.timeline .ai-step strong { color: #8d671b; }

.ai-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  margin-top: 24px;
  padding: 0 18px;
  border-radius: 8px;
  background: var(--ink);
  color: var(--white);
  font-weight: 760;
}

.vietnam-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  background: #ecf2ef;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.contact-section {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 48px;
  align-items: start;
}

.contact-box {
  display: grid;
  gap: 12px;
  padding: 24px;
  background: linear-gradient(180deg, #ffffff, #edf4f6);
  color: var(--ink);
  border: 1px solid rgba(31, 111, 139, 0.18);
  border-radius: 8px;
  box-shadow: 0 14px 34px rgba(31, 55, 65, 0.1);
}
.contact-box strong { font-size: 18px; line-height: 1.5; }
.contact-box a { color: var(--steel); }

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 26px 34px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 1180px) {
  .site-header { grid-template-columns: 1fr auto; }
  .nav { display: none; }
}

@media (max-width: 840px) {
  .hero-panel { max-width: 360px; }
  .intro-band,
  .split-section,
  .delivery-section,
  .vietnam-section,
  .contact-section,
  .line-system-heading,
  .equipment-heading { grid-template-columns: 1fr; }
  .section-heading { position: static; }
  .capability-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .equipment-grid { grid-template-columns: 1fr; }
  .proof-strip { grid-template-columns: 1fr; }
  .proof-strip div { border-right: 0; border-bottom: 1px solid var(--line); }
  .line-map { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 1120px) {
  .hero {
    grid-template-columns: 1fr;
    align-content: end;
    gap: 26px;
    padding: 132px 40px 42px;
  }

  h1 {
    max-width: 780px;
    font-size: clamp(40px, 5.8vw, 58px);
    line-height: 1.08;
  }

  .hero-copy { max-width: 700px; }

  .hero-panel {
    max-width: 620px;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 8px 20px;
  }

  .hero-panel span { align-self: end; }
  .hero-panel strong { margin-bottom: 0; }
}

@media (max-width: 1120px) and (max-height: 720px) {
  .hero {
    min-height: 100vh;
    gap: 16px;
    padding: 118px 40px 28px;
  }

  h1 {
    max-width: 760px;
    font-size: clamp(38px, 5.1vw, 54px);
    line-height: 1.05;
  }

  html[lang="vi"] h1 {
    max-width: 820px;
    font-size: clamp(34px, 4.8vw, 46px);
    line-height: 1.12;
  }

  .hero-copy {
    max-width: 740px;
    font-size: 17px;
    line-height: 1.62;
  }

  .hero-metrics div {
    min-height: 72px;
    padding-top: 10px;
    padding-bottom: 10px;
  }

  .hero-metrics strong { font-size: 24px; }
  .hero-panel { display: none; }
}

@media (max-width: 640px) {
  .site-header { padding: 10px 14px; gap: 10px; }
  .brand { gap: 11px; }
  .brand img { width: 58px; height: 58px; padding: 3px; }
  .brand strong { font-size: 18px; }
  .brand small { font-size: 12px; }
  .language-switch { justify-self: end; }
  .lang-button { padding: 7px 8px; font-size: 12px; }
  .hero { min-height: 86vh; padding: 118px 20px 34px; }
  h1 { font-size: 39px; }
  .hero-copy { font-size: 16px; }
  .hero-metrics { grid-template-columns: 1fr; }
  .hero-metrics div { min-height: 76px; border-right: 0; border-bottom: 1px solid rgba(31, 111, 139, 0.22); }
  .intro-band,
  .section,
  .contact-section,
  .line-system-section,
  .equipment-section { padding: 58px 20px; }
  .equipment-heading,
  .equipment-grid { width: 100%; }
  .equipment-grid article { min-height: auto; }
  .solution-list,
  .capability-grid,
  .line-map { grid-template-columns: 1fr; }
  .timeline li { grid-template-columns: 1fr; gap: 8px; }
  .site-footer { flex-direction: column; padding: 22px 20px; }
}