.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  height: 70px;
  background: #ffffff;
  box-shadow: 0 3px 12px rgba(146, 148, 151, 0.15);
}

.nav-inner {
  display: flex;
  align-items: center;
  height: 70px;
}

.brand {
  display: block;
  width: 105px;
  height: 22px;
  flex: 0 0 auto;
}

.brand img {
  width: 105px;
  height: 22px;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 80px;
  height: 100%;
  margin-left: 140px;
}

.primary-nav a {
  position: relative;
  display: grid;
  align-items: center;
  height: 100%;
  color: #333333;
  font-size: 16px;
  font-weight: 400;
  line-height: 22px;
  white-space: nowrap;
  transition: color 160ms ease;
}

.primary-nav a:hover,
.primary-nav a.is-active {
  color: var(--accent);
}

.primary-nav a.is-active {
  font-weight: 500;
}

.primary-nav a.is-active::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 20px;
  height: 4px;
  border-radius: 2px;
  background: var(--accent);
  transform: translateX(-50%);
}

.hero {
  position: relative;
  height: 580px;
  color: #ffffff;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}

.hero-about {
  background-image: url("../lanhu_source/about/assets/00-hero-banner.webp");
}

.hero-content {
  position: relative;
  width: min(1200px, calc(100% - 48px));
  height: 100%;
  margin-inline: auto;
  text-align: center;
}

.hero h1 {
  position: absolute;
  top: 206px;
  left: 0;
  width: 100%;
  margin: 0;
  color: #ffffff;
  font-size: 52px;
  font-weight: 600;
  line-height: 60px;
}

.hero-cta {
  position: absolute;
  top: 382px;
  left: 50%;
  display: grid;
  place-items: center;
  width: 120px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: 4px;
  color: #ffffff;
  background: rgba(255, 255, 255, 0.24);
  font-size: 16px;
  font-weight: 500;
  line-height: 22px;
  transform: translateX(-50%);
  transition: background-color 160ms ease, transform 160ms ease;
}

.hero-cta:hover {
  background: rgba(255, 255, 255, 0.34);
}

.hero-cta:active {
  transform: translateX(-50%) translateY(1px);
}

.about-intro {
  height: 1006px;
  background: #ffffff;
}

.about-intro-inner {
  position: relative;
  height: 100%;
}

.about-intro h2,
.capabilities-inner > h2,
.contact-inner > h2 {
  margin: 0;
  color: var(--ink);
  font-size: 40px;
  font-weight: 600;
  line-height: 40px;
  text-align: center;
}

.about-intro h2 {
  position: absolute;
  top: 80px;
  left: 0;
  width: 100%;
}

.about-copy {
  position: absolute;
  top: 166px;
  left: 0;
  width: 1187px;
  color: var(--muted);
  font-size: 22px;
  font-weight: 400;
  line-height: 40px;
}

.about-copy p {
  margin: 0;
}

.company-photo {
  position: absolute;
  top: 406px;
  left: 0;
  width: 1200px;
  height: 500px;
  border-radius: 16px;
  object-fit: cover;
}

.capabilities-section {
  height: 740px;
  background: #eaf7ff url("../lanhu_source/about/assets/04-capability-background.webp") center / cover no-repeat;
}

.capabilities-inner {
  position: relative;
  height: 100%;
}

.capabilities-inner > h2 {
  position: absolute;
  top: 100px;
  left: 0;
  width: 100%;
}

.capability-grid {
  position: absolute;
  top: 200px;
  left: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  width: 100%;
}

.capability-card {
  position: relative;
  height: 440px;
  padding: 30px 28px 26px;
  border: 2px solid rgba(255, 255, 255, 0.94);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.34);
}

.capability-card h3 {
  margin: 0;
  color: var(--ink);
  font-size: 28px;
  font-weight: 500;
  line-height: 28px;
  white-space: nowrap;
}

.heading-rule {
  display: block;
  width: 60px;
  height: 6px;
  margin-top: 18px;
  background: var(--accent);
}

.capability-card p {
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 18px;
  font-weight: 400;
  line-height: 30px;
}

.capability-card img {
  position: absolute;
  left: 26px;
  bottom: 26px;
  width: calc(100% - 52px);
  height: 160px;
  border-radius: 12px;
  object-fit: cover;
}

.contact-section {
  height: 580px;
  background: #f4f8fe url("../lanhu_source/about/assets/08-contact-background.webp") center / cover no-repeat;
}

.contact-inner {
  position: relative;
  height: 100%;
}

.contact-inner > h2 {
  position: absolute;
  top: 70px;
  left: 0;
  width: 100%;
}

.contact-intro {
  position: absolute;
  top: 132px;
  left: 0;
  width: 100%;
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  font-weight: 400;
  line-height: 24px;
  text-align: center;
}

.contact-form {
  position: absolute;
  top: 196px;
  left: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 580px;
  transform: translateX(-50%);
}

.contact-form input,
.contact-form textarea {
  width: 580px;
  border: 1px solid transparent;
  border-radius: 4px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 0 14px rgba(111, 120, 133, 0.08);
  font-size: 14px;
  font-weight: 400;
  line-height: 20px;
  transition: border-color 160ms ease, box-shadow 160ms ease;
}

.contact-form input {
  height: 40px;
  padding: 0 16px;
}

.contact-form textarea {
  height: 120px;
  padding: 10px 16px;
  resize: none;
}

.contact-form input + label + input,
.contact-form input + label + textarea {
  margin-top: 20px;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
  color: #6b7280;
  opacity: 1;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: rgba(18, 102, 236, 0.66);
  box-shadow: 0 0 0 3px rgba(18, 102, 236, 0.12);
}

.contact-form .input-error {
  border-color: #d92d20;
}

.submit-btn {
  display: grid;
  place-items: center;
  width: 130px;
  height: 44px;
  margin-top: 20px;
  border-radius: 4px;
  color: #ffffff;
  background: var(--accent);
  font-size: 16px;
  font-weight: 500;
  line-height: 22px;
  cursor: pointer;
  transition: background-color 160ms ease, transform 160ms ease;
}

.submit-btn:hover {
  background: #0b5ddd;
}

.submit-btn:active {
  transform: translateY(1px);
}

.form-status {
  min-height: 20px;
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 20px;
  text-align: center;
}

.form-status.is-error {
  color: #b42318;
}

.form-status.is-success {
  color: #117a44;
}

.site-footer {
  display: grid;
  place-items: center;
  height: 120px;
  padding: 0 20px;
  color: #ffffff;
  background: var(--footer);
}

.site-footer p {
  margin: 0;
  font-size: 12px;
  font-weight: 400;
  line-height: 12px;
  text-align: center;
  white-space: nowrap;
}

@media (max-width: 1279px) {
  .primary-nav {
    margin-left: clamp(40px, 10vw, 120px);
    gap: clamp(28px, 6vw, 72px);
  }

  .about-intro,
  .capabilities-section,
  .contact-section {
    height: auto;
  }

  .about-intro {
    padding: 88px 0;
  }

  .about-intro-inner,
  .capabilities-inner,
  .contact-inner {
    height: auto;
  }

  .about-intro h2,
  .about-copy,
  .company-photo,
  .capabilities-inner > h2,
  .capability-grid,
  .contact-inner > h2,
  .contact-intro,
  .contact-form {
    position: static;
  }

  .about-copy {
    width: 100%;
    margin-top: 46px;
  }

  .company-photo {
    width: 100%;
    height: auto;
    margin-top: 46px;
    aspect-ratio: 12 / 5;
  }

  .capabilities-section {
    padding: 88px 0;
  }

  .capability-grid {
    margin-top: 60px;
  }

  .capability-card {
    min-height: 440px;
    height: auto;
  }

  .capability-card h3 {
    font-size: clamp(21px, 2.2vw, 27px);
  }

  .capability-card p {
    font-size: clamp(15px, 1.55vw, 18px);
    line-height: 26px;
  }

  .contact-section {
    padding: 70px 0 60px;
  }

  .contact-intro {
    margin-top: 22px;
  }

  .contact-form {
    width: min(580px, 100%);
    margin: 40px auto 0;
    transform: none;
  }

  .contact-form input,
  .contact-form textarea {
    width: 100%;
  }
}

@media (max-width: 767px) {
  .site-header,
  .nav-inner {
    height: 64px;
  }

  .brand,
  .brand img {
    width: 86px;
    height: auto;
  }

  .primary-nav {
    justify-content: flex-end;
    gap: 18px;
    margin-left: auto;
  }

  .primary-nav a {
    font-size: 12px;
  }

  .primary-nav a.is-active::after {
    bottom: 1px;
    height: 3px;
  }

  .hero {
    height: 500px;
  }

  .hero-about {
    background-position: 44% center;
  }

  .hero-content {
    width: calc(100% - 40px);
  }

  .hero h1 {
    top: 164px;
    font-size: 34px;
    line-height: 43px;
  }

  .hero-cta {
    top: 292px;
  }

  .about-intro,
  .capabilities-section {
    padding: 64px 0;
  }

  .about-intro h2,
  .capabilities-inner > h2,
  .contact-inner > h2 {
    font-size: 30px;
    line-height: 38px;
  }

  .about-copy {
    margin-top: 34px;
    font-size: 17px;
    line-height: 30px;
  }

  .about-copy p + p {
    margin-top: 18px;
  }

  .company-photo {
    margin-top: 34px;
    border-radius: 12px;
  }

  .capability-grid {
    grid-template-columns: 1fr;
    gap: 20px;
    margin-top: 42px;
  }

  .capability-card {
    min-height: 470px;
    padding: 28px 24px 24px;
    border-radius: 12px;
  }

  .capability-card h3 {
    font-size: 25px;
    line-height: 30px;
  }

  .capability-card p {
    font-size: 16px;
    line-height: 25px;
  }

  .capability-card img {
    left: 24px;
    bottom: 24px;
    width: calc(100% - 48px);
    height: auto;
    aspect-ratio: 334 / 160;
  }

  .contact-section {
    padding: 64px 0 48px;
    background-position: 58% center;
  }

  .contact-intro {
    font-size: 15px;
    line-height: 24px;
  }

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

  .contact-form textarea {
    height: 140px;
  }

  .site-footer {
    height: 104px;
  }

  .site-footer p {
    max-width: 320px;
    font-size: 10px;
    line-height: 16px;
    white-space: normal;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}