:root {
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-soft: #f5f8fa;
  --ink: #101827;
  --ink-strong: #07111f;
  --muted: #536170;
  --line: #dce6ea;
  --line-strong: #cbd9df;
  --teal: #00a6aa;
  --teal-dark: #00858c;
  --cyan: #14c2d4;
  --deep: #071723;
  --deep-2: #0c2533;
  --accent: #d84f44;
  --shadow: 0 18px 50px rgba(20, 49, 68, 0.12);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}

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

img,
svg {
  display: block;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 32px;
  min-height: 76px;
  padding: 0 clamp(20px, 5vw, 64px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(220, 230, 234, 0.75);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: max-content;
  color: var(--ink-strong);
  font-size: 26px;
  font-weight: 800;
  line-height: 1;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  color: var(--teal);
}

.brand-mark svg {
  width: 36px;
  height: 36px;
}

.brand-mark path:first-child {
  fill: currentColor;
  stroke: none;
}

.brand-mark path:last-child {
  fill: none;
  stroke: #fff;
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.desktop-nav {
  display: flex;
  justify-content: center;
  gap: clamp(30px, 5vw, 78px);
  color: #273343;
  font-size: 15px;
  font-weight: 600;
}

.desktop-nav a {
  position: relative;
  padding: 28px 0 24px;
}

.desktop-nav a::after {
  position: absolute;
  left: 50%;
  bottom: 16px;
  width: 0;
  height: 2px;
  background: var(--teal);
  border-radius: 999px;
  content: "";
  transform: translateX(-50%);
  transition: width 160ms ease;
}

.desktop-nav a:hover::after,
.desktop-nav a.is-active::after {
  width: 20px;
}

.header-cta,
.primary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  min-height: 48px;
  padding: 0 24px;
  color: #fff;
  background: linear-gradient(135deg, var(--teal), var(--teal-dark));
  border: 0;
  border-radius: var(--radius);
  box-shadow: 0 16px 34px rgba(0, 166, 170, 0.22);
  font-size: 15px;
  font-weight: 800;
  white-space: nowrap;
}

.header-cta svg,
.primary-button svg {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.header-cta {
  min-height: 44px;
  min-width: 132px;
}

.menu-button,
.mobile-nav {
  display: none;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(420px, 1.1fr);
  align-items: center;
  gap: clamp(24px, 4vw, 64px);
  min-height: calc(100vh - 76px);
  max-width: 1400px;
  margin: 0 auto;
  padding: clamp(54px, 8vw, 104px) clamp(20px, 5vw, 64px) 42px;
  overflow: hidden;
  background:
    radial-gradient(circle at 92% 18%, rgba(20, 194, 212, 0.12), transparent 26%),
    linear-gradient(90deg, rgba(255, 255, 255, 0), rgba(245, 250, 252, 0.92));
}

.hero-copy {
  max-width: 610px;
}

.hero h1 {
  margin: 0;
  color: var(--ink-strong);
  font-size: clamp(54px, 7vw, 92px);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: 0;
}

.hero-lead {
  margin: 28px 0 0;
  color: var(--ink);
  font-size: clamp(24px, 3vw, 36px);
  font-weight: 850;
  line-height: 1.25;
}

.hero-text {
  max-width: 560px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.95;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 22px;
  margin-top: 46px;
}

.primary-button {
  min-width: 178px;
  min-height: 62px;
  padding: 0 34px;
  font-size: 18px;
}

.secondary-link {
  color: var(--teal-dark);
  font-size: 16px;
  font-weight: 800;
}

.hero-visual {
  position: relative;
  min-height: 460px;
}

.hero-visual img {
  width: min(760px, 58vw);
  max-width: none;
  margin-left: -28px;
  filter: drop-shadow(0 26px 48px rgba(9, 26, 40, 0.12));
}

.section-wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 72px 24px;
}

.section-heading {
  max-width: 720px;
  margin: 0 auto 34px;
  text-align: center;
}

.section-heading h2 {
  margin: 0;
  color: var(--ink-strong);
  font-size: clamp(30px, 4vw, 44px);
  font-weight: 900;
  line-height: 1.2;
}

.section-heading p {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.service-card {
  min-height: 218px;
  padding: 36px 30px 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 10px 32px rgba(16, 43, 58, 0.05);
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.service-card:hover {
  border-color: rgba(0, 166, 170, 0.45);
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.service-icon {
  display: grid;
  place-items: center;
  width: 72px;
  height: 72px;
  margin-bottom: 22px;
  color: var(--teal);
  background: rgba(0, 166, 170, 0.08);
  border-radius: var(--radius);
}

.service-icon svg,
.advantage-grid svg,
.contact-band svg {
  width: 42px;
  height: 42px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.service-card h3 {
  margin: 0 0 12px;
  color: var(--ink-strong);
  font-size: 22px;
  line-height: 1.25;
}

.service-card p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.process {
  padding-top: 34px;
}

.process-list {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0;
  margin: 52px 0 42px;
  padding: 0;
  list-style: none;
}

.process-list li {
  position: relative;
  min-height: 140px;
  padding: 0 14px;
  text-align: center;
}

.process-list li::before {
  position: absolute;
  top: 22px;
  left: 0;
  width: 100%;
  border-top: 1px dashed var(--line-strong);
  content: "";
}

.process-list li:first-child::before {
  left: 50%;
  width: 50%;
}

.process-list li:last-child::before {
  width: 50%;
}

.process-list span {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  margin: 0 auto 18px;
  color: var(--teal-dark);
  background: #fff;
  border: 2px solid rgba(0, 166, 170, 0.28);
  border-radius: 50%;
  font-size: 14px;
  font-weight: 900;
}

.process-list strong {
  display: block;
  color: var(--ink-strong);
  font-size: 17px;
}

.process-list p {
  margin: 8px auto 0;
  max-width: 140px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.65;
}

.advantage-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.advantage-grid div {
  display: grid;
  grid-template-columns: 54px 1fr;
  column-gap: 18px;
  padding: 28px 24px;
}

.advantage-grid div + div {
  border-left: 1px solid var(--line);
}

.advantage-grid svg {
  grid-row: span 2;
  color: var(--teal);
}

.advantage-grid strong {
  color: var(--ink-strong);
  font-size: 19px;
}

.advantage-grid p {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.contact-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 40px;
  padding: 58px clamp(24px, 7vw, 96px);
  color: #fff;
  background:
    linear-gradient(90deg, rgba(7, 23, 35, 0.98), rgba(8, 50, 66, 0.9)),
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0 1px, transparent 1px 42px);
}

.contact-band h2 {
  margin: 0;
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 900;
}

.contact-band p {
  max-width: 630px;
  margin: 14px 0 0;
  color: rgba(255, 255, 255, 0.76);
  font-size: 17px;
}

.contact-actions {
  display: flex;
  align-items: center;
  gap: 28px;
}

.mail-card {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  min-width: 300px;
  color: #fff;
}

.mail-card svg {
  width: 52px;
  height: 52px;
}

.mail-card small {
  display: block;
  color: rgba(255, 255, 255, 0.68);
  font-size: 14px;
}

.mail-card span {
  font-size: 17px;
  font-weight: 700;
}

.primary-button.light {
  min-height: 54px;
  font-size: 16px;
}

.site-footer {
  display: grid;
  grid-template-columns: minmax(260px, 1.35fr) minmax(130px, 0.55fr) minmax(250px, 0.8fr);
  gap: 54px;
  padding: 58px clamp(24px, 7vw, 96px) 28px;
  color: rgba(255, 255, 255, 0.78);
  background: linear-gradient(130deg, var(--deep), var(--deep-2));
}

.brand.inverse {
  color: #fff;
}

.footer-brand p {
  max-width: 360px;
  margin: 20px 0 0;
  font-size: 15px;
}

.footer-links,
.footer-contact {
  display: grid;
  align-content: start;
  gap: 10px;
}

.footer-links strong,
.footer-contact strong {
  margin-bottom: 6px;
  color: #fff;
  font-size: 18px;
}

.footer-links a,
.footer-contact a {
  width: fit-content;
  color: rgba(255, 255, 255, 0.74);
  font-size: 15px;
}

.footer-links a:hover,
.footer-contact a:hover,
.footer-bottom a:hover {
  color: #fff;
}

.footer-bottom {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  gap: 28px 72px;
  margin-top: 18px;
  padding-top: 22px;
  border-top: 1px solid rgba(255, 255, 255, 0.11);
  color: rgba(255, 255, 255, 0.66);
  font-size: 14px;
}

.back-to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 18;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  color: #fff;
  background: #050b10;
  border-radius: 50%;
  box-shadow: 0 14px 32px rgba(5, 11, 16, 0.2);
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 160ms ease, transform 160ms ease;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

@media (max-width: 1080px) {
  .site-header {
    gap: 18px;
  }

  .desktop-nav {
    gap: 30px;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 70px;
  }

  .hero-copy {
    max-width: 720px;
  }

  .hero-visual {
    min-height: auto;
  }

  .hero-visual img {
    width: min(780px, 100%);
    margin: 0 auto;
  }

  .process-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    row-gap: 30px;
  }

  .process-list li:nth-child(3)::before,
  .process-list li:nth-child(6)::before {
    width: 50%;
  }

  .process-list li:nth-child(4)::before {
    left: 50%;
    width: 50%;
  }

  .contact-band,
  .site-footer {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 820px) {
  .site-header {
    grid-template-columns: 1fr auto;
    min-height: 68px;
  }

  .brand {
    font-size: 22px;
  }

  .brand-mark,
  .brand-mark svg {
    width: 32px;
    height: 32px;
  }

  .desktop-nav,
  .header-cta {
    display: none;
  }

  .menu-button {
    display: grid;
    place-items: center;
    width: 42px;
    height: 42px;
    padding: 0;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
  }

  .menu-button span {
    width: 18px;
    height: 2px;
    background: var(--ink);
    border-radius: 99px;
  }

  .menu-button span + span {
    margin-top: -16px;
  }

  .mobile-nav {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    z-index: 19;
    display: grid;
    gap: 2px;
    padding: 12px 20px 18px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 18px 40px rgba(11, 34, 49, 0.12);
    transform: translateY(-120%);
    transition: transform 180ms ease;
  }

  .mobile-nav.is-open {
    transform: translateY(0);
  }

  .mobile-nav a {
    padding: 13px 0;
    color: var(--ink);
    font-size: 16px;
    font-weight: 750;
  }

  .hero {
    padding-top: 54px;
  }

  .hero h1 {
    font-size: clamp(46px, 14vw, 68px);
  }

  .hero-lead {
    font-size: 25px;
  }

  .hero-text {
    font-size: 16px;
  }

  .primary-button {
    min-height: 56px;
    width: 100%;
  }

  .secondary-link {
    width: 100%;
    text-align: center;
  }

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

  .advantage-grid div + div {
    border-top: 1px solid var(--line);
    border-left: 0;
  }

  .process-list {
    grid-template-columns: 1fr;
    gap: 16px;
    margin-top: 36px;
  }

  .process-list li {
    display: grid;
    grid-template-columns: 54px 1fr;
    align-items: start;
    min-height: auto;
    padding: 0;
    text-align: left;
  }

  .process-list li::before {
    display: none;
  }

  .process-list span {
    margin: 0;
  }

  .process-list p {
    grid-column: 2;
    max-width: none;
    margin-left: 0;
  }

  .contact-actions {
    display: grid;
    gap: 22px;
  }

  .mail-card {
    min-width: 0;
  }

  .contact-band {
    padding: 48px 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}