:root {
  --ground: #f3f4f6;
  --ink: #1e252b;
  --blue: #1b3faf;
  --line: #d7dce1;
  --muted: #59616b;
  --header-height: 95px;
  --category-offset: 190px;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 0;
}
body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font:
    16px/1.65 -apple-system,
    "PingFang SC",
    "Microsoft YaHei",
    "Segoe UI",
    sans-serif;
}
a {
  color: inherit;
  text-underline-offset: 5px;
}
button {
  font: inherit;
  cursor: pointer;
}
button,
a {
  -webkit-tap-highlight-color: transparent;
}
button:focus-visible,
a:focus-visible {
  outline: 3px solid #2f7fd8;
  outline-offset: 5px;
}
::selection {
  background: #1b3faf;
  color: white;
}
img {
  max-width: 100%;
  display: block;
}
h1,
h2,
h3,
p {
  margin: 0;
}
h1,
h2,
h3 {
  line-height: 1.25;
  text-wrap: balance;
}
h1 {
  font-size: clamp(34px, 3.8vw, 56px);
  letter-spacing: -0.025em;
}
h2 {
  font-size: 32px;
  letter-spacing: -0.02em;
}
h3 {
  font-size: 21px;
}
p {
  max-width: 70ch;
}
.wrap {
  width: min(1280px, calc(100% - 96px));
  margin-inline: auto;
}
.header {
  position: sticky;
  top: 0;
  z-index: 25;
  background: white;
  border-bottom: 1px solid var(--line);
}
.header-inner {
  min-height: 94px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 13px;
  text-decoration: none;
}

.brand img {
  width: auto;
  object-fit: contain;
}
.brand .logo-achel,
.footer-brand img:first-child {
  height: 56px;
}
.brand .logo-altek,
.footer-brand img:last-child {
  height: 30px;
}
.brand-sep {
  width: 1px;
  height: 34px;
  background: var(--line, #d9dde2);
  flex: 0 0 auto;
}
.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav a {
  text-decoration: none;
  padding-block: 12px;
  border-bottom: 2px solid transparent;
}
.nav a[aria-current] {
  color: var(--blue);
  border-color: var(--blue);
}
.language {
  background: white;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 9px 14px;
  color: var(--blue);
  min-height: 44px;
}
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
  align-items: center;
  min-height: clamp(560px, calc(100svh - 220px), 680px);
  gap: 24px;
}
.hero .company {
  color: var(--muted);
  margin-bottom: 23px;
  font-size: 19px;
}
.hero h1 span {
  display: block;
}
.hero .intro {
  margin: 22px 0 30px;
  color: var(--muted);
}
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 11px 21px;
  border-radius: 6px;
  background: var(--blue);
  border: 1px solid var(--blue);
  color: white;
  text-decoration: none;
  font-weight: 600;
}
.button.secondary {
  color: var(--blue);
  background: transparent;
}
.button:hover {
  background: #14318b;
  color: white;
}
.section {
  padding-block: 64px;
}
.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}
.section-head a {
  color: var(--blue);
}
.category-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
}
.category-tile {
  text-decoration: none;
  border-top: 1px solid #bbc2ca;
  display: block;
  padding-top: 16px;
}
.category-tile img {
  height: 200px;
  width: 100%;
  object-fit: contain;
  margin-bottom: 16px;
  transition: transform 0.2s;
}
.category-tile:hover img {
  transform: translateY(-4px);
}
.category-tile h3 {
  font-size: 19px;
  margin-bottom: 12px;
}
.numeric {
  font-family: "DIN Alternate", "Bahnschrift", "DIN", sans-serif;
  font-variant-numeric: tabular-nums;
}
.range {
  font-size: 30px;
  line-height: 1.3;
}
.ports {
  display: inline-flex;
  gap: 4px;
  vertical-align: middle;
  margin-right: 9px;
}
.ports i {
  width: 6px;
  height: 6px;
  border-radius: 100%;
  background: #d8352a;
}
.ports i + i {
  background: #2f7fd8;
}
.contact-section {
  background: white;
}
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
}
.contact-item {
  border-top: 1px solid var(--line);
  padding-top: 22px;
}
.contact-item h3 {
  margin-bottom: 8px;
}
.contact-number {
  font-size: clamp(24px, 2.5vw, 32px);
  display: inline-block;
  text-decoration: none;
  white-space: nowrap;
  margin-bottom: 10px;
}
.contact-details {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  color: var(--muted);
}
.copy {
  border: 1px solid #bec6d0;
  background: transparent;
  color: var(--blue);
  border-radius: 6px;
  padding: 6px 13px;
  min-height: 44px;
}
.contact-details a {
  color: var(--blue);
}
.footer {
  background: white;
  border-top: 1px solid var(--line);
  padding: 36px 0 22px;
}
.footer-top {
  display: flex;
  justify-content: space-between;
  gap: 35px;
  align-items: start;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 16px;
}
.footer-brand img {
  width: auto;
  max-width: none;
  object-fit: contain;
}
.footer-contacts {
  display: flex;
  gap: 44px;
  font-size: 14px;
}
.footer-contacts a {
  display: block;
}
.footer .copy {
  font-size: 12px;
  margin-top: 8px;
  min-height: 36px;
}
.footer-bottom {
  border-top: 1px solid var(--line);
  margin-top: 30px;
  padding-top: 18px;
  color: var(--muted);
  font-size: 12px;
}
.page-head {
  padding: 60px 0 32px;
}
.page-head p {
  color: var(--muted);
  margin-top: 18px;
}
.category-nav {
  position: sticky;
  top: var(--header-height);
  z-index: 24;
  background: var(--ground);
  padding-block: 12px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 32px;
}
.category-nav a {
  background: white;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 14px 12px;
  text-decoration: none;
  text-align: center;
  font-size: 14px;
}
.category-nav a[aria-current="location"] {
  background: var(--blue);
  border-color: var(--blue);
  color: white;
}
.category-nav a:not([aria-current]):hover {
  border-color: var(--blue);
  color: var(--blue);
}
.product-section {
  scroll-margin-top: var(--category-offset);
  padding: 30px 0 50px;
  border-top: 1px solid var(--line);
}
.product-section h2 {
  margin-bottom: 28px;
}
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
}
.product-grid.storage {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}
.product-grid.tanks {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
.product-card {
  min-width: 0;
}
.image-button {
  display: block;
  border: 0;
  padding: 0;
  width: 100%;
  background: #edeff2;
  border-radius: 6px;
  position: relative;
}
.image-button img {
  width: 100%;
  height: 300px;
  object-fit: contain;
}
.storage .image-button img {
  height: 260px;
}
.image-hint {
  position: absolute;
  bottom: 10px;
  right: 12px;
  font-size: 12px;
  color: #515a65;
  background: white;
  padding: 3px 9px;
  border-radius: 4px;
}
.product-card h3 {
  margin: 22px 0 12px;
}
.product-card .feature {
  color: var(--muted);
  font-size: 14px;
  margin-top: 16px;
}
.specs {
  margin: 0;
}
.specs dt {
  font-size: 14px;
  color: var(--muted);
  margin-top: 13px;
}
.specs dd {
  margin: 2px 0 0;
  overflow-wrap: anywhere;
}
.specs .numeric {
  font-size: 20px;
  line-height: 1.45;
}
.note {
  color: #5e4b32;
  font-size: 12px;
  margin-top: 12px;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
table {
  border-collapse: collapse;
  width: 100%;
  font-variant-numeric: tabular-nums;
}
th,
td {
  text-align: left;
  border-bottom: 1px solid var(--line);
  padding: 8px 12px;
}
th {
  font-weight: 600;
  font-size: 14px;
}
td {
  font:
    17px/1.4 "DIN Alternate",
    "Bahnschrift",
    "DIN",
    sans-serif;
}
.contact-page {
  padding-bottom: 60px;
}
.mobile-bar {
  display: none;
}
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  max-width: calc(100% - 32px);
  width: max-content;
  background: var(--ink);
  color: white;
  border-radius: 6px;
  padding: 12px 20px;
  z-index: 30;
  font-size: 14px;
}
.toast:empty {
  display: none;
}
dialog {
  border: 0;
  border-radius: 6px;
  padding: 18px;
  width: min(850px, calc(100% - 32px));
  max-height: 90dvh;
  background: var(--ground);
  color: var(--ink);
}
dialog::backdrop {
  background: rgba(20, 27, 35, 0.78);
}
.dialog-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}
.dialog-close {
  background: white;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 6px 14px;
  min-height: 44px;
}
.dialog-image {
  width: 100%;
  height: min(65dvh, 650px);
  object-fit: contain;
}
.dialog-caption {
  font-size: 14px;
  color: var(--muted);
}
body.modal-open {
  overflow: hidden;
}
.skip {
  position: absolute;
  left: 20px;
  top: -90px;
  background: white;
  padding: 12px;
  z-index: 100;
}
.skip:focus {
  top: 10px;
}

.about-page {
  padding-bottom: 40px;
}

@media (max-width: 900px) {
  .wrap {
    width: calc(100% - 48px);
  }
  .nav {
    gap: 18px;
  }
  .hero {
    min-height: 480px;
    grid-template-columns: 1fr 1fr;
  }
  .hero h1 {
    font-size: 36px;
  }
  .category-grid {
    gap: 16px;
  }
  .category-tile img {
    height: 155px;
  }
  .product-grid.storage {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .product-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .footer-contacts {
    gap: 20px;
  }
  .contact-grid {
    gap: 25px;
  }
}
@media (max-width: 600px) {
  .wrap {
    width: calc(100% - 40px);
  }
  .header-inner {
    min-height: 112px;
    gap: 8px;
    flex-wrap: wrap;
    padding-block: 12px;
  }
  .brand .logo-achel {
    height: 44px;
  }
  .brand .logo-altek {
    height: 24px;
  }
  .brand-sep {
    height: 28px;
  }
  .nav {
    order: 3;
    width: 100%;
    justify-content: space-between;
    gap: 10px;
    font-size: 14px;
  }
  .nav a {
    padding: 4px 0;
  }
  .language {
    font-size: 13px;
    padding: 5px 10px;
    min-height: 36px;
  }
  .hero {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 24px;
    padding-top: 32px;
    min-height: 0;
  }
  .hero .company {
    font-size: 15px;
    margin-bottom: 16px;
  }
  .hero h1 {
    font-size: 38px;
  }
  .hero .intro {
    font-size: 14px;
    margin: 18px 0 23px;
  }
  .hero .button {
    font-size: 14px;
    padding-inline: 16px;
  }
  .section {
    padding-block: 40px;
  }
  h2 {
    font-size: 26px;
  }
  .section-head {
    gap: 16px;
    margin-bottom: 23px;
  }
  .section-head a {
    font-size: 13px;
  }
  .category-grid {
    grid-template-columns: 1fr 1fr;
    gap: 28px 18px;
  }
  .category-tile img {
    height: 170px;
  }
  .category-tile h3 {
    font-size: 16px;
    min-height: 40px;
  }
  .range {
    font-size: 26px;
  }
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  .contact-number {
    font-size: 28px;
  }
  .contact-details {
    font-size: 14px;
    gap: 10px;
  }
  .footer {
    padding-bottom: 94px;
  }
  .footer-top {
    display: block;
  }
  .footer-contacts {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    margin-top: 24px;
  }
  .footer-bottom {
    font-size: 12px;
  }
  .mobile-bar {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: white;
    border-top: 1px solid var(--line);
    padding-bottom: env(safe-area-inset-bottom);
    z-index: 20;
  }
  .mobile-bar a,
  .mobile-bar button {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 60px;
    border: 0;
    background: white;
    color: var(--blue);
    text-decoration: none;
    font-size: 14px;
    gap: 8px;
  }
  .mobile-bar > * + * {
    border-left: 1px solid var(--line) !important;
  }
  .mobile-bar svg {
    width: 18px;
    height: 18px;
  }
  .toast {
    bottom: 78px;
  }
  .page-head {
    padding: 37px 0 25px;
  }
  .page-head h1 {
    font-size: 34px;
  }
  .page-head p {
    font-size: 14px;
  }
  .category-nav {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }
  .category-nav a {
    font-size: 13px;
    padding: 10px 6px;
  }
  .product-section {
    scroll-margin-top: var(--category-offset);
    padding: 26px 0 36px;
  }
  .product-grid,
  .product-grid.tanks {
    grid-template-columns: 1fr;
    gap: 26px;
  }
  .product-grid.storage,
  .product-grid.boilers {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px 14px;
  }
  .image-button img {
    height: 230px;
  }
  .storage .image-button img,
  .boilers .image-button img {
    height: 180px;
  }
  .product-card h3 {
    font-size: 19px;
    margin-top: 14px;
  }
  .storage h3,
  .boilers h3 {
    font-size: 17px;
  }
  .specs .numeric {
    font-size: 18px;
  }
  .specs dt {
    font-size: 13px;
    margin-top: 8px;
  }
  .specs dd {
    font-size: 14px;
  }
  .storage .specs .numeric,
  .boilers .specs .numeric {
    font-size: 16px;
  }
  .product-card .feature,
  .product-card .note {
    font-size: 13px;
    margin-top: 10px;
  }
  .image-hint {
    font-size: 13px;
    right: 8px;
    bottom: 8px;
  }
  .contact-page {
    padding-bottom: 40px;
  }
  .dialog-top {
    font-size: 14px;
  }
  .dialog-close {
    font-size: 13px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}

/* R3：保留既有配色、DIN 数字、小圆角，扩展三语与真实工厂素材。 */
.languages {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}
.language {
  font-size: 14px;
  padding: 8px 10px;
}
.language[aria-pressed="true"] {
  background: var(--blue);
  color: white;
  border-color: var(--blue);
}
.header-inner {
  gap: 22px;
}
.nav {
  gap: 24px;
}
.nav a,
.language,
.dialog-close {
  white-space: nowrap;
}
.hero {
  padding-block: 40px;
  gap: 40px;
}
.hero h1 {
  font-size: clamp(32px, 3.2vw, 48px);
}
.hero-photo img {
  height: clamp(350px, 38vw, 520px);
  width: 100%;
  object-fit: cover;
  border-radius: 6px;
}
.hero .intro {
  font-size: 19px;
}
.category-tile,
.product-card,
.factory-layout > *,
.export-section > *,
.custom-section > * {
  min-width: 0;
}
.category-tile h3 {
  hyphens: auto;
  overflow-wrap: break-word;
}
.category-tile .range {
  font-size: clamp(20px, 2vw, 28px);
}
.option-note {
  font-size: 14px;
  color: var(--muted);
  margin-top: 10px;
}
.custom-section,
.export-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 60px;
  border-top: 1px solid var(--line);
}
.custom-section p,
.export-section p {
  margin-top: 18px;
  color: var(--muted);
}
.service-list {
  margin: 0;
  padding-inline-start: 22px;
}
.service-list li {
  padding: 7px 0 7px 4px;
}
.service-list li::marker {
  color: var(--blue);
}
.section-intro {
  margin-bottom: 24px;
  color: var(--muted);
}
.factory-layout {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}
.factory-gallery {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}
.factory-gallery figure,
.video-block,
.series-images figure {
  margin: 0;
  min-width: 0;
}
.factory-gallery figure:first-child {
  grid-row: span 2;
}
.factory-gallery figure:first-child img {
  height: 510px;
}
.factory-photo img {
  height: 220px;
  width: 100%;
  object-fit: cover;
  border-radius: 6px;
}
.home-gallery {
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
}
.home-gallery figure:first-child img {
  height: 480px;
}
.home-gallery .factory-photo img {
  height: 207px;
}
.home-gallery figure:first-child img {
  height: 480px;
}
figcaption {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.45;
  padding-top: 9px;
}
.video-block video {
  display: block;
  width: 100%;
  max-height: 560px;
  aspect-ratio: 9 / 16;
  background: var(--ink);
  object-fit: contain;
  border-radius: 6px;
}
.about-page > .section > .video-block {
  max-width: 330px;
}
.company-profile {
  max-width: 900px;
}
.company-profile h2 {
  font-size: 26px;
  margin-bottom: 24px;
}
.company-profile p {
  max-width: 75ch;
  margin-bottom: 20px;
}
.capability-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
}
.capability-grid h2 {
  margin-bottom: 20px;
}
.tank-features {
  padding: 0 0 28px;
}
.tank-features .service-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 40px;
}
.product-grid,
.product-grid.storage,
.product-grid.tanks {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 40px 32px;
  align-items: start;
}
.product-grid.boilers {
  grid-template-columns: 1fr;
}
.product-card {
  border-top: 1px solid var(--line);
  padding-top: 20px;
}
.series-images {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px 10px;
}
.series-images:has(> :last-child:nth-child(-n + 3)) {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
.series-images:has(> :last-child:nth-child(-n + 2)) {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
.series-images:has(> :only-child) {
  grid-template-columns: 1fr;
}
.series-images .image-button img {
  height: 190px;
  object-fit: contain;
}
.series-images .small-source img {
  height: 190px;
  max-width: 230px;
  margin-inline: auto;
}
.series-images .image-hint {
  font-size: 11px;
  padding: 2px 5px;
  bottom: 6px;
  right: 6px;
}
.series-images figcaption {
  text-align: center;
  overflow-wrap: break-word;
  font-size: 13px;
}
.boilers .series-images {
  max-width: 800px;
}
.models {
  color: var(--muted);
  font-size: 15px;
  margin-bottom: 12px;
  overflow-wrap: break-word;
}
.summary-specs .numeric {
  font-size: 20px;
}
.full-specs {
  margin-top: 22px;
  min-width: 0;
  background: white;
  border-radius: 6px;
}
summary {
  cursor: pointer;
  color: var(--blue);
  padding: 14px 16px;
  font-weight: 600;
  line-height: 1.5;
}
summary:focus-visible,
.table-scroll:focus-visible {
  outline: 3px solid #2f7fd8;
  outline-offset: 2px;
}
.performance-specs {
  margin: 0;
  padding: 4px 16px 16px;
}
.performance-specs > div {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.4fr);
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
}
.performance-specs dt,
.performance-specs dd {
  margin: 0;
  font-size: 14px;
  overflow-wrap: break-word;
}
.performance-specs dt {
  color: var(--muted);
}
.table-scroll {
  overflow-x: auto;
  max-width: 100%;
  border-radius: 0 0 6px 6px;
  overscroll-behavior-inline: contain;
  scrollbar-color: #929ca7 var(--ground);
}
.parameter-table {
  min-width: 640px;
}
.parameter-table thead,
.parameter-table tbody th {
  background: #edeff2;
}
.parameter-table td {
  white-space: nowrap;
  font-size: 15px;
}
.parameter-table th {
  min-width: 105px;
}
.parameter-table th:first-child {
  min-width: 170px;
  max-width: 220px;
}
.dialog-image {
  margin-top: 14px;
}
@media (max-width: 1100px) {
  .header-inner {
    flex-wrap: wrap;
    padding-block: 12px;
    gap: 8px 20px;
  }
  .nav {
    order: 3;
    width: 100%;
    justify-content: space-between;
  }
  .factory-layout {
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
  }
}
@media (max-width: 700px) {
  .header-inner {
    min-height: 0;
  }
  .brand {
    gap: 7px;
  }
  .brand .logo-achel {
    height: 38px;
  }
  .brand .logo-altek {
    height: 20px;
  }
  .brand-sep {
    height: 26px;
  }
  .language {
    position: static;
    font-size: 13px;
    padding: 7px 6px;
    min-height: 40px;
  }
  .languages {
    gap: 3px;
  }
  .nav {
    gap: 12px;
    font-size: 14px;
  }
  .hero {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    min-height: 0;
    padding: 32px 0 0;
    gap: 24px;
  }
  .hero h1 {
    font-size: 34px;
    overflow-wrap: break-word;
  }
  .hero .intro {
    font-size: 16px;
  }
  .hero-photo img {
    height: 320px;
  }
  .category-grid {
    grid-template-columns: 1fr 1fr;
  }
  .category-tile h3 {
    min-height: 0;
    font-size: 17px;
  }
  .category-tile .range {
    font-size: 21px;
  }
  .section-head {
    align-items: start;
    flex-wrap: wrap;
  }
  .custom-section,
  .export-section,
  .capability-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .factory-layout {
    grid-template-columns: 1fr;
  }
  .factory-gallery {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
    gap: 18px 12px;
  }
  .factory-gallery figure:first-child {
    grid-row: auto;
    grid-column: 1 / -1;
  }
  .factory-gallery figure:first-child img,
  .home-gallery figure:first-child img {
    height: 300px;
  }
  .factory-photo img,
  .home-gallery .factory-photo img {
    height: 160px;
  }
  .factory-gallery figure:first-child img {
    height: 300px;
  }
  .video-block {
    max-width: 240px;
    width: 100%;
    margin-inline: auto;
  }
  .tank-features .service-list {
    grid-template-columns: 1fr;
  }
  .product-grid,
  .product-grid.storage,
  .product-grid.tanks,
  .product-grid.boilers {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .series-images .image-button img {
    height: 150px;
  }
  .series-images {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .series-images .image-hint {
    position: static;
    display: block;
    font-size: 12px;
    padding-block: 5px;
  }
  .series-images:has(> :only-child) .image-button img {
    height: 230px;
  }
  .series-images .small-source img {
    max-width: 200px;
  }
  .full-specs {
    margin-top: 18px;
  }
  .category-nav a {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    hyphens: auto;
  }
  .company-profile h2 {
    font-size: 24px;
    overflow-wrap: break-word;
  }
}
@media (max-width: 360px) {
  .wrap {
    width: calc(100% - 28px);
  }
  .brand .logo-achel {
    height: 32px;
  }
  .brand .logo-altek {
    height: 17px;
  }
  .language {
    padding-inline: 4px;
  }
  .nav {
    font-size: 13px;
    gap: 8px;
  }
  .contact-number {
    font-size: 25px;
  }
}

/* 2026-11-11 Claude：关于我们的三条生产线配图、三段工厂视频 */
.production-lines {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}
.production-lines figure {
  margin: 0;
}
.production-lines .image-button img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 6px;
}
.production-lines figcaption {
  font-size: 15px;
  font-weight: 600;
  padding-top: 10px;
}
.video-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 280px));
  gap: 20px;
}
.video-row .video-block {
  max-width: none;
  margin: 0;
}
@media (max-width: 760px) {
  .production-lines {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .video-row {
    grid-template-columns: repeat(3, 70%);
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    padding-bottom: 6px;
  }
  .video-row .video-block {
    scroll-snap-align: start;
    max-width: none;
  }
}

/* 2026-11-11 Claude：加上美国电话和两个邮箱，联系方式变成 4 组 */
.contact-emails {
  display: grid;
  gap: 8px;
  margin-top: 4px;
}
.contact-email {
  font-size: clamp(17px, 1.6vw, 20px);
  color: var(--blue);
  overflow-wrap: anywhere;
}
@media (min-width: 601px) {
  .footer-contacts {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, auto));
    gap: 22px 44px;
  }
}
.footer-contacts a {
  overflow-wrap: anywhere;
}