:root {
  --ink: #17191c;
  --muted: #6d7480;
  --paper: #ffffff;
  --soft: #f3f5f8;
  --line: #e5e9ef;
  --blue: #2d526c;
  --orange: #f28c16;
  --footer: #f6f7f9;
  --max: 1380px;
  --header: 76px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family:
    Arial, Helvetica, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  line-height: 1.55;
}

body.nav-open {
  overflow: hidden;
}

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

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

button {
  font: inherit;
  cursor: pointer;
}

main,
section,
footer {
  scroll-margin-top: calc(var(--header) + 20px);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
}

.nav-shell {
  width: min(var(--max), calc(100% - 44px));
  min-height: var(--header);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 150px;
  color: var(--ink);
  font-size: clamp(1.35rem, 2vw, 2.05rem);
  font-weight: 900;
  letter-spacing: 0;
}

.brand-mark {
  position: relative;
  width: 38px;
  height: 30px;
  display: inline-block;
  overflow: hidden;
}

.brand-mark i {
  position: absolute;
  top: 0;
  width: 19px;
  height: 30px;
  background: var(--orange);
  transform: skewX(-26deg);
}

.brand-mark i:first-child {
  left: 3px;
}

.brand-mark i:last-child {
  left: 18px;
  background: #8d99a6;
}

.nav-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(13px, 1.6vw, 25px);
  color: #23262b;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
}

.nav-links a {
  min-height: var(--header);
  display: inline-flex;
  align-items: center;
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  border-color: var(--orange);
  color: var(--orange);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  background: #fff;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 5px auto;
  background: var(--ink);
}

.hero-grid {
  width: min(var(--max), calc(100% - 44px));
  margin: 28px auto 0;
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0;
  background: #fff;
}

.feature-tile {
  position: relative;
  min-height: 320px;
  overflow: hidden;
  grid-column: span 2;
  border: 1px solid #fff;
  background: #dfe3e8;
}

.feature-tile.tile-wide {
  min-height: 370px;
  grid-column: span 3;
}

.feature-tile a,
.feature-tile img {
  height: 100%;
}

.feature-tile a {
  position: relative;
  display: block;
}

.feature-tile img {
  object-fit: cover;
  transition: transform 500ms ease;
}

.feature-tile img.is-missing {
  min-height: inherit;
  background:
    linear-gradient(135deg, rgba(45, 82, 108, 0.14), rgba(242, 140, 22, 0.12)),
    #edf1f5;
}

.feature-tile img.is-missing::after {
  content: "";
}

.feature-tile::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(15, 17, 19, 0.06), rgba(15, 17, 19, 0.32)),
    linear-gradient(90deg, rgba(15, 17, 19, 0.16), transparent 56%);
  pointer-events: none;
}

.feature-tile span {
  position: absolute;
  left: 26px;
  bottom: 23px;
  z-index: 2;
  color: #fff;
  font-size: clamp(1.55rem, 3.2vw, 3rem);
  font-weight: 800;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  text-shadow: 0 8px 28px rgba(0, 0, 0, 0.35);
}

.feature-tile:hover img {
  transform: scale(1.045);
}

.profile-strip {
  width: min(var(--max), calc(100% - 44px));
  margin: 36px auto 0;
  padding: 28px 0 8px;
  display: grid;
  grid-template-columns: minmax(260px, 0.58fr) minmax(300px, 0.42fr);
  gap: 28px;
  align-items: end;
  border-bottom: 1px solid var(--line);
}

.profile-strip p,
.section-heading p,
.service-band p {
  margin: 0;
  color: var(--orange);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.profile-strip h1,
.section-heading h2,
.service-band h2 {
  margin: 7px 0 0;
  color: #11141a;
  font-size: clamp(1.8rem, 4vw, 4rem);
  line-height: 1.06;
  letter-spacing: 0;
}

.profile-strip > p {
  color: var(--muted);
  font-size: 0.98rem;
  font-weight: 500;
  letter-spacing: 0;
  text-transform: none;
}

.catalog-section {
  width: min(var(--max), calc(100% - 44px));
  margin: 76px auto 0;
}

.section-heading {
  display: grid;
  gap: 7px;
  max-width: 760px;
  margin-bottom: 26px;
}

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

.catalog-grid article {
  min-height: 210px;
  display: grid;
  align-content: start;
  gap: 12px;
  padding: 28px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: #fff;
}

.catalog-grid span {
  color: var(--orange);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.18em;
}

.catalog-grid h3,
.catalog-grid p {
  margin: 0;
}

.catalog-grid h3 {
  font-size: 1.45rem;
}

.catalog-grid p {
  color: var(--muted);
}

.service-band {
  width: min(var(--max), calc(100% - 44px));
  margin: 78px auto 0;
  min-height: 190px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: center;
  padding: 34px;
  background:
    linear-gradient(90deg, rgba(18, 22, 27, 0.86), rgba(18, 22, 27, 0.58)),
    url("https://www.wellbo.com.cn/images/s2.jpg") center / cover;
  color: #fff;
}

.service-band h2 {
  max-width: 760px;
  color: #fff;
}

.service-band a {
  min-height: 44px;
  display: inline-grid;
  place-items: center;
  padding: 0 24px;
  border: 1px solid #fff;
  color: #fff;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.service-band a:hover {
  background: #fff;
  color: var(--ink);
}

.site-footer {
  margin-top: 62px;
  background: var(--footer);
  color: #343942;
}

.footer-inner {
  width: min(var(--max), calc(100% - 44px));
  margin: 0 auto;
  padding: 44px 0;
  display: grid;
  grid-template-columns: 0.9fr 0.9fr 0.9fr 1.55fr;
  gap: clamp(22px, 4vw, 66px);
}

.footer-inner nav,
.footer-inner address {
  display: grid;
  align-content: start;
  gap: 10px;
  font-style: normal;
}

.footer-inner a,
.footer-inner span {
  color: #737985;
  font-size: 0.9rem;
}

.footer-inner a:first-child,
.footer-inner strong {
  color: #222831;
  font-weight: 800;
}

.footer-inner a:hover {
  color: var(--orange);
}

.copyright {
  border-top: 1px solid var(--line);
  min-height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  padding: 10px 18px;
  color: #8a9099;
  font-size: 0.82rem;
  text-align: center;
}

.copyright a {
  color: #737985;
}

.back-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 50;
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border: 0;
  background: rgba(23, 25, 28, 0.84);
  color: #fff;
  font-size: 1.5rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 180ms ease;
}

.back-top.is-visible {
  opacity: 1;
  pointer-events: auto;
}

@media (max-width: 1180px) {
  .nav-shell {
    width: calc(100% - 28px);
  }

  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    left: 0;
    top: 100%;
    right: 0;
    display: grid;
    align-content: start;
    gap: 0;
    max-height: calc(100vh - var(--header));
    overflow: auto;
    border-top: 1px solid var(--line);
    background: #fff;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition:
      opacity 180ms ease,
      transform 180ms ease;
  }

  body.nav-open .nav-links {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-links a {
    min-height: 48px;
    padding: 0 20px;
    border-bottom: 1px solid var(--line);
  }
}

@media (max-width: 900px) {
  .hero-grid,
  .profile-strip,
  .catalog-section,
  .service-band,
  .footer-inner {
    width: calc(100% - 28px);
  }

  .hero-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .feature-tile,
  .feature-tile.tile-wide {
    min-height: 290px;
    grid-column: span 1;
  }

  .profile-strip,
  .service-band {
    grid-template-columns: 1fr;
  }

  .catalog-grid,
  .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 620px) {
  :root {
    --header: 64px;
  }

  .brand {
    min-width: auto;
    font-size: 1.36rem;
  }

  .brand-mark {
    width: 34px;
    height: 26px;
  }

  .brand-mark i {
    width: 17px;
    height: 26px;
  }

  .hero-grid {
    margin-top: 14px;
    grid-template-columns: 1fr;
  }

  .feature-tile,
  .feature-tile.tile-wide {
    min-height: 245px;
  }

  .feature-tile span {
    left: 18px;
    bottom: 18px;
  }

  .catalog-grid,
  .footer-inner {
    grid-template-columns: 1fr;
  }

  .service-band {
    padding: 24px;
  }
}