:root {
  --ink: #10131a;
  --ink-soft: #25303a;
  --muted: #68717a;
  --line: #dde3e6;
  --paper: #ffffff;
  --wash: #f4f7f6;
  --deep: #0a1012;
  --gold: #d6a51d;
  --gold-soft: #f2d46f;
  --green: #0c6f62;
  --green-soft: #dceee9;
  --shadow: 0 18px 48px rgba(11, 18, 22, 0.14);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
}

body.nav-open {
  overflow: hidden;
}

img {
  max-width: 100%;
  display: block;
}

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

button,
input,
textarea {
  font: inherit;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 42px;
  color: #fff;
  background: rgba(9, 13, 16, 0.72);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(14px);
  transition: background 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled {
  background: rgba(8, 12, 14, 0.94);
  box-shadow: 0 12px 34px rgba(0, 0, 0, 0.24);
}

.brand {
  width: 232px;
  min-width: 180px;
}

.brand img {
  width: 100%;
  height: auto;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 30px;
  font-size: 15px;
}

.site-nav a {
  position: relative;
  color: rgba(255, 255, 255, 0.86);
  padding: 8px 0;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: #fff;
}

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255, 255, 255, 0.24);
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius);
  padding: 10px;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: #fff;
  margin: 5px 0;
}

.hero {
  position: relative;
  min-height: 82vh;
  overflow: hidden;
  color: #fff;
  display: flex;
  align-items: center;
  padding: 120px 42px 76px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(5, 9, 11, 0.9) 0%, rgba(8, 13, 16, 0.68) 44%, rgba(8, 13, 16, 0.2) 100%),
    linear-gradient(0deg, rgba(5, 9, 11, 0.56), rgba(5, 9, 11, 0.06)),
    url("./assets/hero-project.jpg") center / cover no-repeat;
  transform: scale(1.02);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(760px, 100%);
  margin: 0 auto;
  max-width: var(--max);
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--gold);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  font-size: 64px;
  line-height: 1.08;
  font-weight: 800;
}

.hero h1 span {
  display: block;
}

.hero-lead {
  margin: 22px 0 0;
  color: var(--gold-soft);
  font-size: 27px;
  font-weight: 700;
}

.hero-lead span {
  display: block;
}

.hero-lead span + span {
  margin-top: 6px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 19px;
  font-weight: 600;
}

.hero-copy {
  max-width: 680px;
  margin: 22px 0 0;
  color: rgba(255, 255, 255, 0.84);
  font-size: 18px;
}

.hero-actions,
.contact-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-weight: 700;
  line-height: 1.2;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button.primary {
  color: #111;
  background: var(--gold);
}

.button.ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.46);
  background: rgba(255, 255, 255, 0.06);
}

.button.light {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.35);
}

.metric-strip {
  position: relative;
  z-index: 2;
  max-width: var(--max);
  margin: -36px auto 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--paper);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.metric-strip div {
  min-height: 116px;
  padding: 24px 28px;
  border-right: 1px solid var(--line);
}

.metric-strip div:last-child {
  border-right: 0;
}

.metric-strip strong {
  display: block;
  color: var(--green);
  font-size: 30px;
  line-height: 1.1;
}

.metric-strip span {
  display: block;
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
}

.section {
  padding: 96px 42px;
}

.section-heading {
  width: min(var(--max), 100%);
  margin: 0 auto 42px;
  display: grid;
  grid-template-columns: 0.9fr 1.35fr;
  gap: 60px;
  align-items: end;
}

.section-heading.compact {
  display: block;
  max-width: var(--max);
}

.section-heading h2,
.contact h2,
.client-panel h2 {
  margin: 0;
  color: var(--ink);
  font-size: 38px;
  line-height: 1.25;
}

.intro-grid,
.advantage-list,
.project-grid,
.culture-grid,
.service-grid,
.contact-inner,
.client-panel {
  width: min(var(--max), 100%);
  margin: 0 auto;
}

.intro {
  background: linear-gradient(180deg, #fff 0%, var(--wash) 100%);
}

.intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.75fr);
  gap: 54px;
  align-items: stretch;
}

.intro-copy {
  padding-top: 8px;
  color: var(--ink-soft);
  font-size: 18px;
}

.intro-copy p {
  margin: 0 0 20px;
}

.mission-block {
  min-height: 340px;
  padding: 36px;
  color: #fff;
  background: linear-gradient(145deg, #101515, #18372f);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
}

.mission-block img {
  width: 112px;
  opacity: 0.95;
}

.mission-block p {
  margin: auto 0 12px;
  color: var(--gold-soft);
  font-weight: 700;
}

.mission-block h3 {
  margin: 0;
  font-size: 29px;
  line-height: 1.35;
}

.services {
  background: var(--deep);
  color: #fff;
}

.services .section-heading h2 {
  color: #fff;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-top: 1px solid rgba(255, 255, 255, 0.16);
  border-left: 1px solid rgba(255, 255, 255, 0.16);
}

.service-grid article {
  min-height: 300px;
  padding: 30px 24px;
  border-right: 1px solid rgba(255, 255, 255, 0.16);
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
}

.service-grid span {
  display: inline-flex;
  color: var(--gold);
  font-size: 14px;
  font-weight: 800;
  margin-bottom: 34px;
}

.service-grid h3,
.advantage-list h3,
.project-card h3,
.culture-grid h3 {
  margin: 0;
  font-size: 21px;
  line-height: 1.35;
}

.service-grid p {
  margin: 18px 0 0;
  color: rgba(255, 255, 255, 0.72);
  font-size: 15px;
}

.advantages {
  background: #fff;
}

.advantage-list {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.advantage-list article {
  min-height: 240px;
  padding: 28px;
  background: var(--wash);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.advantage-list h3 {
  color: var(--green);
}

.advantage-list p {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 15px;
}

.projects {
  background: #eef4f2;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.project-card {
  min-height: 430px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 12px 28px rgba(16, 19, 26, 0.07);
}

.project-card.wide {
  grid-column: span 2;
}

.project-card img {
  width: 100%;
  height: 280px;
  object-fit: cover;
}

.project-card div {
  padding: 22px 24px 26px;
}

.project-card p {
  margin: 0 0 8px;
  color: var(--green);
  font-size: 13px;
  font-weight: 800;
}

.project-card span {
  display: block;
  margin-top: 12px;
  color: var(--muted);
  font-size: 14px;
}

.clients {
  background: #fff;
}

.client-panel {
  padding: 42px;
  background: var(--ink);
  color: #fff;
  border-radius: var(--radius);
  display: grid;
  grid-template-columns: 0.7fr 1.3fr;
  gap: 42px;
}

.client-panel h2 {
  color: #fff;
}

.client-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
}

.client-columns ul {
  margin: 0;
  padding-left: 18px;
  color: rgba(255, 255, 255, 0.76);
}

.client-columns li {
  margin: 0 0 12px;
}

.culture {
  background: var(--wash);
}

.culture-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.culture-grid article {
  min-height: 284px;
  padding: 30px 26px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.culture-grid strong {
  display: block;
  margin-bottom: 26px;
  color: var(--gold);
  font-size: 48px;
  line-height: 1;
}

.culture-grid p {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 15px;
}

.contact {
  padding: 92px 42px;
  color: #fff;
  background:
    linear-gradient(90deg, rgba(9, 14, 16, 0.94), rgba(12, 48, 42, 0.86)),
    url("./assets/case-industrial.jpg") center / cover no-repeat;
}

.contact-inner {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 60px;
  align-items: center;
}

.contact h2 {
  color: #fff;
}

.contact p {
  max-width: 680px;
  margin: 18px 0 0;
  color: rgba(255, 255, 255, 0.78);
  font-size: 17px;
}

.contact-actions {
  margin-top: 0;
  justify-content: flex-end;
}

.contact-panel {
  padding: 28px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius);
}

.contact-list {
  margin: 0 0 26px;
  color: #fff;
}

.contact-list div {
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: 18px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
}

.contact-list div:first-child {
  padding-top: 0;
}

.contact-list dt {
  color: var(--gold-soft);
  font-weight: 800;
}

.contact-list dd {
  margin: 0;
  color: rgba(255, 255, 255, 0.86);
}

.contact-list a {
  color: #fff;
  font-weight: 800;
}

.contact-actions span {
  width: 100%;
  color: rgba(255, 255, 255, 0.68);
  text-align: right;
  font-size: 14px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  padding: 28px 42px;
  color: rgba(255, 255, 255, 0.64);
  background: #080c0e;
  font-size: 13px;
}

.site-footer img {
  width: 210px;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 1080px) {
  .site-header {
    padding: 0 28px;
  }

  .site-nav {
    gap: 20px;
  }

  .hero {
    padding-left: 28px;
    padding-right: 28px;
  }

  .hero h1 {
    font-size: 52px;
  }

  .metric-strip {
    margin-left: 28px;
    margin-right: 28px;
  }

  .section,
  .contact {
    padding-left: 28px;
    padding-right: 28px;
  }

  .section-heading,
  .intro-grid,
  .contact-inner,
  .client-panel {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .service-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .advantage-list,
  .culture-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .project-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-actions {
    justify-content: flex-start;
  }

  .contact-actions span {
    text-align: left;
  }
}

@media (max-width: 760px) {
  .site-header {
    height: 68px;
    padding: 0 18px;
  }

  .brand {
    width: 178px;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    display: none;
    padding: 18px;
    background: rgba(8, 12, 14, 0.98);
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  }

  .site-nav.is-open {
    display: grid;
    gap: 8px;
  }

  .site-nav a {
    padding: 12px 4px;
  }

  .hero {
    min-height: 84vh;
    padding: 104px 20px 70px;
  }

  .hero-bg {
    background:
      linear-gradient(90deg, rgba(5, 9, 11, 0.92) 0%, rgba(8, 13, 16, 0.74) 58%, rgba(8, 13, 16, 0.38) 100%),
      linear-gradient(0deg, rgba(5, 9, 11, 0.62), rgba(5, 9, 11, 0.08)),
      url("./assets/hero-project.jpg") center / cover no-repeat;
  }

  .hero h1 {
    font-size: 38px;
  }

  .hero-lead {
    font-size: 22px;
  }

  .hero-copy,
  .intro-copy,
  .contact p {
    font-size: 16px;
  }

  .hero-actions {
    align-items: stretch;
  }

  .button {
    width: 100%;
  }

  .metric-strip {
    margin: -28px 18px 0;
    grid-template-columns: repeat(2, 1fr);
  }

  .metric-strip div {
    min-height: 108px;
    padding: 20px 18px;
    border-bottom: 1px solid var(--line);
  }

  .metric-strip div:nth-child(2) {
    border-right: 0;
  }

  .section,
  .contact {
    padding: 72px 18px;
  }

  .section-heading h2,
  .contact h2,
  .client-panel h2 {
    font-size: 29px;
  }

  .intro-grid,
  .service-grid,
  .advantage-list,
  .project-grid,
  .culture-grid,
  .client-columns {
    grid-template-columns: 1fr;
  }

  .mission-block {
    min-height: 300px;
    padding: 28px;
  }

  .service-grid article {
    min-height: auto;
  }

  .project-card.wide {
    grid-column: auto;
  }

  .project-card {
    min-height: auto;
  }

  .project-card img {
    height: 220px;
  }

  .contact-list div {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .client-panel {
    padding: 28px;
  }

  .site-footer {
    display: grid;
    padding: 26px 18px;
  }

  .site-footer img {
    width: 180px;
  }
}

@media (max-width: 420px) {
  .hero h1 {
    font-size: 32px;
  }

  .metric-strip {
    grid-template-columns: 1fr;
  }

  .metric-strip div {
    border-right: 0;
  }
}