:root {
  --ink: #16201f;
  --muted: #64716f;
  --line: #d9e1de;
  --paper: #f7f8f4;
  --soft: #edf2ee;
  --teal: #0f7b72;
  --teal-dark: #07524f;
  --amber: #c88a31;
  --white: #ffffff;
  --shadow: 0 18px 50px rgba(17, 32, 30, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

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

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(20px, 5vw, 72px);
  color: var(--white);
  transition: background 180ms ease, color 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  color: var(--ink);
  background: rgba(247, 248, 244, 0.94);
  box-shadow: 0 8px 30px rgba(16, 26, 25, 0.08);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand-mark {
  width: 58px;
  height: 42px;
  object-fit: contain;
  object-position: left center;
  flex: 0 0 auto;
}

.brand strong,
.brand small {
  display: block;
  white-space: nowrap;
}

.brand strong {
  font-size: 15px;
}

.brand small {
  color: currentColor;
  font-size: 11px;
  opacity: 0.72;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 14px;
}

.site-nav a {
  opacity: 0.86;
}

.site-nav a:hover {
  opacity: 1;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid currentColor;
  background: transparent;
  color: inherit;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 92vh;
  overflow: hidden;
  color: var(--white);
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(11, 22, 21, 0.88), rgba(11, 22, 21, 0.62) 42%, rgba(11, 22, 21, 0.1) 100%),
    linear-gradient(0deg, rgba(11, 22, 21, 0.35), rgba(11, 22, 21, 0));
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(780px, calc(100% - 40px));
  padding: 168px 0 96px clamp(20px, 5vw, 72px);
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--amber);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 0;
  font-size: clamp(40px, 6vw, 76px);
  line-height: 1.06;
  letter-spacing: 0;
}

h2 {
  margin: 0;
  font-size: clamp(28px, 4vw, 48px);
  line-height: 1.18;
  letter-spacing: 0;
}

h3 {
  margin: 0 0 12px;
  font-size: 20px;
  line-height: 1.25;
}

.hero-lead {
  max-width: 680px;
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.84);
  font-size: clamp(16px, 1.6vw, 20px);
}

.hero-actions,
.contact-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 22px;
  border: 1px solid transparent;
  font-weight: 700;
  transition: transform 160ms ease, background 160ms ease, color 160ms ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn.primary {
  color: var(--white);
  background: var(--teal);
}

.btn.ghost {
  color: var(--white);
  border-color: rgba(255, 255, 255, 0.62);
}

.btn.ghost-dark {
  color: var(--ink);
  border-color: rgba(22, 32, 31, 0.24);
}

.section {
  padding: 96px clamp(20px, 5vw, 72px);
}

.intro {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 1fr);
  gap: 48px;
  align-items: center;
}

.intro-copy h2 {
  max-width: 680px;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid var(--line);
  background: var(--white);
  box-shadow: var(--shadow);
}

.metrics div {
  padding: 28px;
  border-right: 1px solid var(--line);
}

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

.metrics strong {
  display: block;
  color: var(--teal-dark);
  font-size: 30px;
  line-height: 1;
}

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

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 0.7fr) minmax(260px, 0.55fr);
  gap: 36px;
  align-items: end;
  margin-bottom: 42px;
}

.section-heading p:last-child {
  margin: 0;
  color: var(--muted);
}

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

.service-card {
  min-height: 300px;
  padding: 28px;
  border: 1px solid var(--line);
  background: var(--white);
}

.service-card p,
.work-list p,
.timeline p,
.about-points p,
.contact-panel p {
  color: var(--muted);
}

.card-number {
  display: inline-block;
  margin-bottom: 54px;
  color: var(--amber);
  font-weight: 800;
}

.work-band {
  color: var(--white);
  background: var(--teal-dark);
}

.work-band .section-heading p:last-child,
.work-list p {
  color: rgba(255, 255, 255, 0.72);
}

.work-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: rgba(255, 255, 255, 0.24);
}

.work-list div {
  min-height: 260px;
  padding: 30px;
  background: var(--teal-dark);
}

.timeline {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.timeline li {
  position: relative;
  padding: 28px 24px;
  border-top: 3px solid var(--teal);
  background: var(--soft);
}

.timeline span {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  margin-bottom: 30px;
  color: var(--white);
  background: var(--teal);
  font-weight: 800;
}

.about {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(280px, 0.7fr);
  gap: 52px;
  align-items: start;
  background: var(--white);
}

.about-points {
  display: grid;
  gap: 16px;
}

.about-points p {
  margin: 0;
  padding: 20px 0 20px 22px;
  border-left: 3px solid var(--amber);
}

.contact {
  padding: 96px clamp(20px, 5vw, 72px);
  background:
    linear-gradient(135deg, rgba(15, 123, 114, 0.18), rgba(200, 138, 49, 0.16)),
    var(--paper);
}

.contact-panel {
  max-width: 900px;
  padding: clamp(30px, 5vw, 54px);
  background: var(--white);
  box-shadow: var(--shadow);
}

.contact-panel h2 {
  max-width: 700px;
}

.contact-panel p {
  max-width: 680px;
}

.contact-note {
  margin-top: 20px;
  font-size: 13px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 28px clamp(20px, 5vw, 72px);
  color: rgba(255, 255, 255, 0.72);
  background: #111817;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 980px) {
  .service-grid,
  .timeline {
    grid-template-columns: repeat(2, 1fr);
  }

  .intro,
  .section-heading,
  .about {
    grid-template-columns: 1fr;
  }

  .work-list {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .site-header {
    padding: 14px 18px;
  }

  .brand strong {
    max-width: 210px;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .brand-mark {
    width: 48px;
  }

  .nav-toggle {
    display: block;
    flex: 0 0 auto;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    left: 18px;
    right: 18px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    color: var(--ink);
    background: var(--white);
    box-shadow: var(--shadow);
  }

  .site-nav.is-open {
    display: flex;
  }

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

  .hero {
    min-height: 86vh;
  }

  .hero-shade {
    background: linear-gradient(90deg, rgba(11, 22, 21, 0.9), rgba(11, 22, 21, 0.62));
  }

  .hero-content {
    width: calc(100% - 36px);
    padding: 130px 0 70px 18px;
  }

  .section,
  .contact {
    padding: 68px 18px;
  }

  .metrics,
  .service-grid,
  .timeline {
    grid-template-columns: 1fr;
  }

  .metrics div {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .metrics div:last-child {
    border-bottom: 0;
  }

  .service-card {
    min-height: 0;
  }

  .card-number {
    margin-bottom: 34px;
  }

  .site-footer {
    flex-direction: column;
  }
}