:root {
  --black: #050505;
  --ink: #111827;
  --muted: #5d6675;
  --line: #d9dde5;
  --paper: #f5f6f8;
  --white: #ffffff;
  --red: #e31b23;
  --blue: #0067b8;
  --teal: #0b817c;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--white);
}

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

.site-header {
  position: fixed;
  top: 0;
  z-index: 20;
  width: 100%;
  background: rgba(0, 0, 0, 0.92);
  color: var(--white);
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 0 42px;
}

.menu-button {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  background: transparent;
}

.menu-button span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--white);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
}

.brand-logo {
  width: auto;
  height: 40px;
  display: block;
}

.brand-name {
  font-size: 25px;
  white-space: nowrap;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 40px;
  font-size: 22px;
  font-weight: 700;
  transform: none;
}

.main-nav .hotline {
  font-size: 20px;
  white-space: nowrap;
  transform: none;
}

.main-nav a,
.quote-link {
  opacity: 0.9;
}

.main-nav a:hover,
.quote-link:hover {
  opacity: 1;
}

.quote-link {
  padding: 11px 16px;
  border: 1px solid rgba(255, 255, 255, 0.45);
  font-weight: 700;
}

.hero {
  position: relative;
  min-height: 760px;
  color: var(--white);
  overflow: hidden;
  background: var(--black);
}

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

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(0, 0, 0, 0.78), rgba(0, 0, 0, 0.32) 48%, rgba(0, 0, 0, 0.12)),
    linear-gradient(0deg, rgba(0, 0, 0, 0.86), rgba(0, 0, 0, 0) 38%);
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(720px, 100%);
  padding: 270px 42px 120px;
}

.eyebrow {
  margin: 0 0 18px;
  color: #d7e8ff;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.eyebrow.dark {
  color: var(--blue);
}

.hero h1 {
  margin: 0;
  font-size: 50px;
  line-height: 0.98;
  letter-spacing: 0;
  max-width: 100%;
  overflow-wrap: anywhere;
}

.hero-copy {
  max-width: 100%;
  margin: 80px 0 0;
  color: #edf2f7;
  font-size: 20px;
  line-height: 1.6;
}

.section {
  padding: 52px 42px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  max-width: 1220px;
  margin: 0 auto 28px;
}

.section-heading h2,
.company-section h2,
.feature-dark h2,
.contact-section h2 {
  margin: 0;
  font-size: clamp(32px, 4vw, 54px);
  line-height: 1.05;
  letter-spacing: 0;
}

.section-heading a {
  color: var(--blue);
  font-weight: 800;
}

#products {
  padding-top: 32px;
  padding-bottom: 20px;
}

.company-section {
  padding-top: 24px;
}

#products .section-heading h2 {
  font-size: 50px;
}

.news-band {
  background: var(--paper);
  padding-top: 36px;
  padding-bottom: 30px;
}

.news-band .section-heading h2 {
  font-size: 30px;
}

.news-band .section-heading {
  margin-bottom: 14px;
}

.history-flow {
  display: grid;
  grid-template-columns: repeat(6, minmax(180px, 1fr));
  gap: 0;
  max-width: 1220px;
  margin: 0 auto;
  overflow: hidden;
  background: var(--white);
  border: 1px solid var(--line);
}

.history-flow article,
.product-card {
  min-height: 230px;
  padding: 24px;
  background: var(--white);
  border-top: 4px solid var(--red);
  box-shadow: 0 1px 0 var(--line);
}

.history-flow article {
  position: relative;
  min-height: 310px;
  padding: 0;
  border-top: 0;
  border-right: 1px solid var(--line);
  box-shadow: none;
}

.history-photo {
  position: absolute;
  inset: 0;
  background-image: url("./assets/history-timeline-v2.webp");
  background-repeat: no-repeat;
  background-position: var(--history-position) center;
  background-size: 600% auto;
}

.history-flow article::before {
  content: "";
  position: absolute;
  inset: 45% 0 0;
  z-index: 1;
  background: linear-gradient(to bottom, transparent, rgb(0 0 0 / 88%));
}

.history-flow article:last-child {
  border-right: 0;
}

.history-flow article::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -13px;
  z-index: 2;
  width: 26px;
  height: 26px;
  border-top: 1px solid var(--line);
  border-right: 1px solid var(--line);
  background: var(--white);
  transform: rotate(45deg);
}

.history-flow article:last-child::after {
  display: none;
}

.history-flow span {
  position: absolute;
  left: 18px;
  bottom: 64px;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  margin-bottom: 0;
  padding: 0 10px;
  background: var(--black);
  color: var(--white);
  font-size: 12px;
  font-weight: 900;
}

.history-flow strong {
  position: absolute;
  right: 18px;
  bottom: 22px;
  left: 18px;
  z-index: 2;
  display: block;
  margin-bottom: 0;
  color: var(--white);
  font-size: 23px;
  line-height: 1.15;
}

.news-grid h3,
.product-card h3 {
  margin: 10px 0 14px;
  font-size: 23px;
  line-height: 1.22;
}

.lead-story h3 {
  font-size: 34px;
}

.tag,
time {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}

.news-grid p,
.product-card p,
.company-copy p,
.contact-section p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
}

.split-layout {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 68px;
  max-width: 1220px;
  margin: 0 auto;
}

.company-copy p:first-child {
  margin-top: 0;
}

.metric-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  max-width: 1220px;
  margin: 36px auto 0;
  background: var(--line);
}

.metric-row div {
  padding: 26px;
  background: var(--paper);
}

.metric-row strong {
  display: block;
  margin-bottom: 6px;
  color: var(--blue);
  font-size: 38px;
}

.metric-row span {
  color: var(--muted);
  font-weight: 700;
}

.feature-dark {
  padding: 0;
  background: var(--black);
}

.feature-dark img {
  display: block;
  width: 100%;
  height: auto;
}

.feature-inner {
  max-width: 760px;
}

.feature-inner p:last-child {
  color: #d7dee8;
  font-size: 20px;
  line-height: 1.65;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 1220px;
  margin: 0 auto;
}

.product-card {
  min-height: 0;
  padding: 0;
  border-top-color: var(--blue);
  overflow: hidden;
  cursor: pointer;
}

.product-card:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 3px;
}

.product-card img {
  display: block;
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
}

.product-card h3 {
  min-height: 68px;
  margin: 0;
  padding: 18px 20px;
  display: flex;
  align-items: center;
}

.contact-section {
  display: grid;
  grid-template-columns: 0.8fr 1fr;
  gap: 52px;
  max-width: 1220px;
  margin: 0 auto;
}

.contact-form {
  display: grid;
  gap: 18px;
}

.contact-details {
  margin-top: 34px;
}

.contact-details h3 {
  margin: 0 0 22px;
  font-size: 24px;
  line-height: 1.35;
}

.contact-details dl {
  display: grid;
  gap: 12px;
  margin: 0;
}

.contact-details dl div {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 12px;
}

.contact-details dt {
  color: var(--muted);
  font-weight: 800;
}

.contact-details dd {
  margin: 0;
  color: var(--ink);
  overflow-wrap: anywhere;
}

.contact-details a:hover {
  color: var(--blue);
}

.contact-form label {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-weight: 800;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  border: 1px solid var(--line);
  padding: 14px 15px;
  font: inherit;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: 2px solid var(--blue);
  outline-offset: 1px;
}

.contact-form button {
  min-height: 50px;
  border: 0;
  background: var(--red);
  color: var(--white);
  font: inherit;
  font-weight: 900;
  cursor: pointer;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 32px;
  padding: 36px 42px;
  background: var(--black);
  color: var(--white);
}

.site-footer p {
  color: #aab4c2;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(110px, 1fr));
  gap: 14px 28px;
  font-weight: 800;
}

@media (max-width: 900px) {
  .topbar {
    padding: 0 20px;
  }

  .menu-button {
    display: block;
  }

  .main-nav {
    position: fixed;
    top: 72px;
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 12px 20px 20px;
    background: rgba(0, 0, 0, 0.96);
    transform: none;
  }

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

  .main-nav a {
    width: 100%;
    padding: 14px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  }

  .main-nav .hotline {
    transform: none;
  }

  .quote-link {
    display: none;
  }

  .brand-name {
    font-size: 18px;
  }

  .brand-logo {
    width: auto;
    height: 36px;
  }

  .hero {
    min-height: 820px;
  }

  .hero-content {
    padding: 240px 20px 100px;
  }

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

  .hero-copy {
    font-size: 18px;
  }

  .section,
  .feature-dark {
    padding: 40px 20px;
  }

  .feature-dark {
    padding: 0;
  }

  .news-band {
    padding-top: 28px;
    padding-bottom: 24px;
  }

  #products {
    padding-top: 28px;
  }

  .company-section {
    padding-top: 24px;
  }

  .section-heading,
  .split-layout,
  .contact-section,
  .site-footer {
    display: grid;
    grid-template-columns: 1fr;
  }

  .history-flow,
  .news-grid,
  .product-grid,
  .metric-row {
    grid-template-columns: 1fr;
  }

  .history-flow article {
    display: block;
    min-height: 250px;
    padding: 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .history-photo {
    width: auto;
    height: auto;
    min-height: 0;
    margin: 0;
  }

  .history-flow span {
    width: max-content;
    margin-bottom: 0;
  }

  .history-flow strong {
    margin-bottom: 0;
  }

  .history-flow article::after {
    top: auto;
    right: 34px;
    bottom: -13px;
    transform: rotate(135deg);
  }

  .lead-story h3 {
    font-size: 27px;
  }

  .site-footer {
    padding: 30px 20px;
  }
}