:root {
  --ink: #152033;
  --muted: #5d6678;
  --line: #dfe5ee;
  --paper: #ffffff;
  --soft: #f4f6f9;
  --soft-2: #eef3f7;
  --accent: #f3b21a;
  --accent-dark: #b67a00;
  --steel: #2f6f8f;
  --deep: #1f2d3d;
  --shadow: 0 18px 48px rgba(24, 38, 56, 0.16);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

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

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

button,
input,
select,
textarea {
  font: inherit;
}

.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 76px;
  padding: 14px clamp(18px, 4vw, 56px);
  color: #fff;
  transition: background 180ms ease, box-shadow 180ms ease, color 180ms ease;
}

.site-header.is-solid {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 10px 32px rgba(21, 32, 51, 0.12);
  backdrop-filter: blur(12px);
}

.brand {
  display: flex;
  align-items: center;
  min-width: 0;
  gap: 12px;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 52px;
  height: 38px;
  border: 2px solid currentColor;
  border-left: 8px solid var(--accent);
  color: inherit;
  font-weight: 900;
  line-height: 1;
}

.brand-text {
  display: grid;
  min-width: 0;
}

.brand-text strong {
  max-width: clamp(220px, 30vw, 420px);
  overflow: hidden;
  font-size: 15px;
  font-weight: 800;
  line-height: 1.2;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.brand-text span {
  color: currentColor;
  font-size: 12px;
  opacity: 0.78;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.site-nav a {
  border-radius: 4px;
  padding: 8px 12px;
  color: currentColor;
  font-size: 14px;
  font-weight: 700;
}

.site-nav a:hover {
  background: rgba(255, 255, 255, 0.16);
}

.site-header.is-solid .site-nav a:hover {
  background: var(--soft);
}

.language-switch {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  margin-left: 6px;
  border: 1px solid currentColor;
  border-radius: 4px;
  padding: 2px;
}

.language-switch a {
  padding: 5px 8px;
  font-size: 12px;
  line-height: 1.1;
}

.language-switch a[aria-current="page"] {
  color: #111820;
  background: var(--accent);
}

.site-header.is-solid .language-switch a[aria-current="page"] {
  color: #111820;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid currentColor;
  border-radius: 4px;
  color: inherit;
  background: transparent;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 82vh;
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #fff;
  background: #1d2734;
}

.hero-image,
.hero-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-image {
  object-fit: cover;
}

.hero-overlay {
  background:
    linear-gradient(90deg, rgba(12, 18, 27, 0.9) 0%, rgba(12, 18, 27, 0.74) 42%, rgba(12, 18, 27, 0.3) 100%),
    linear-gradient(0deg, rgba(12, 18, 27, 0.86) 0%, rgba(12, 18, 27, 0.12) 48%);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 98px 0 32px;
}

.eyebrow,
.section-kicker,
.tag {
  margin: 0 0 10px;
  color: var(--accent-dark);
  font-size: 13px;
  font-weight: 900;
  line-height: 1.3;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: var(--accent);
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 18px;
  font-size: 52px;
  line-height: 1.08;
  font-weight: 900;
}

h2 {
  margin-bottom: 16px;
  font-size: 36px;
  line-height: 1.22;
}

h3 {
  margin-bottom: 10px;
  font-size: 21px;
  line-height: 1.28;
}

.hero-lede {
  max-width: 720px;
  color: rgba(255, 255, 255, 0.88);
  font-size: 18px;
}

.hero-actions,
.form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: 4px;
  padding: 11px 18px;
  font-weight: 800;
  line-height: 1.2;
  cursor: pointer;
}

.button-primary {
  color: #121820;
  background: var(--accent);
  border-color: var(--accent);
}

.button-primary:hover {
  background: #ffc94d;
}

.button-ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.72);
  background: rgba(255, 255, 255, 0.08);
}

.button-ghost:hover {
  border-color: #fff;
  background: rgba(255, 255, 255, 0.18);
}

.button-secondary {
  color: var(--ink);
  border-color: var(--line);
  background: var(--paper);
}

.button-secondary:hover {
  border-color: var(--steel);
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 170px));
  gap: 1px;
  max-width: 560px;
  margin: 28px 0 0;
  background: rgba(255, 255, 255, 0.24);
}

.hero-metrics div {
  padding: 15px 18px;
  background: rgba(13, 19, 28, 0.58);
}

.hero-metrics dt {
  color: var(--accent);
  font-size: 30px;
  font-weight: 900;
  line-height: 1;
}

.hero-metrics dd {
  margin: 8px 0 0;
  color: rgba(255, 255, 255, 0.78);
  font-size: 13px;
}

.section {
  padding: 88px 0;
}

.section-band {
  padding: 56px 0;
  background: var(--deep);
  color: #fff;
}

.section-muted {
  background: var(--soft);
}

.section-inner {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.intro-grid {
  display: grid;
  grid-template-columns: 0.86fr 1.14fr;
  gap: 56px;
  align-items: start;
}

.intro-grid h2 {
  color: #fff;
}

.intro-grid p:last-child {
  margin: 30px 0 0;
  color: rgba(255, 255, 255, 0.82);
  font-size: 17px;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 42px;
}

.section-heading p:last-child {
  color: var(--muted);
  font-size: 17px;
}

.capability-layout {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 34px;
  align-items: stretch;
}

.media-panel {
  margin: 0;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.media-panel img {
  width: 100%;
  height: 100%;
  min-height: 420px;
  object-fit: cover;
}

.media-panel figcaption {
  border-top: 1px solid var(--line);
  padding: 12px 16px;
  color: var(--muted);
  font-size: 13px;
  background: var(--paper);
}

.capability-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.insight-grid,
.solution-matrix,
.review-grid,
.faq-grid {
  display: grid;
  gap: 16px;
}

.insight-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.solution-matrix {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

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

.review-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.capability-list article,
.insight-grid article,
.solution-matrix article,
.review-grid article,
.product-card,
.process-grid article,
.qa-list article,
.faq-grid details,
.lead-form {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
}

.capability-list article,
.insight-grid article,
.solution-matrix article,
.review-grid article,
.qa-list article {
  padding: 24px;
}

.capability-list span,
.insight-grid span,
.process-grid span {
  display: inline-grid;
  place-items: center;
  width: 36px;
  height: 36px;
  margin-bottom: 18px;
  border-radius: 4px;
  color: #111820;
  background: var(--accent);
  font-weight: 900;
}

.capability-list p,
.insight-grid p,
.solution-matrix p,
.review-grid p,
.product-card p,
.process-grid p,
.quality-layout p,
.qa-list p,
.faq-grid p,
.contact-copy p {
  color: var(--muted);
}

.solution-matrix ul {
  display: grid;
  gap: 9px;
  margin: 18px 0 0;
  padding-left: 18px;
  color: var(--muted);
}

.solution-matrix li::marker {
  color: var(--accent-dark);
}

.review-grid article {
  position: relative;
  overflow: hidden;
}

.review-grid article::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  left: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--steel));
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.product-card {
  overflow: hidden;
  min-width: 0;
}

.product-card img {
  width: 100%;
  aspect-ratio: 1.25;
  object-fit: cover;
  background: var(--soft-2);
}

.product-card div {
  padding: 20px;
}

.tag {
  margin-bottom: 8px;
  color: var(--steel);
  font-size: 12px;
}

.welder-feature {
  display: grid;
  grid-template-columns: 0.92fr 1.08fr;
  gap: 28px;
  align-items: stretch;
  margin-top: 34px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(243, 178, 26, 0.13), rgba(47, 111, 143, 0.09)),
    var(--paper);
}

.welder-copy {
  align-self: center;
}

.welder-copy p {
  color: var(--muted);
}

.feature-points {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.feature-points span {
  border: 1px solid rgba(47, 111, 143, 0.22);
  border-radius: 4px;
  padding: 7px 10px;
  color: var(--deep);
  background: rgba(255, 255, 255, 0.72);
  font-size: 13px;
  font-weight: 800;
}

.welder-photo {
  overflow: hidden;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--soft);
}

.welder-photo img {
  width: 100%;
  height: calc(100% - 42px);
  min-height: 320px;
  object-fit: cover;
}

.welder-photo figcaption,
.drawing-grid figcaption {
  min-height: 42px;
  padding: 10px 12px;
  color: var(--muted);
  background: #fff;
  font-size: 13px;
  line-height: 1.35;
}

.model-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.model-grid article {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
}

.model-grid p:last-child {
  color: var(--muted);
}

.spec-block {
  display: grid;
  grid-template-columns: 0.45fr 1fr;
  gap: 28px;
  margin-top: 34px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
}

.spec-block p {
  color: var(--muted);
}

.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 640px;
}

th,
td {
  border-bottom: 1px solid var(--line);
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
}

th {
  color: #fff;
  background: var(--deep);
  font-size: 14px;
}

td {
  color: var(--muted);
  font-size: 14px;
}

td:first-child {
  color: var(--ink);
  font-weight: 800;
}

.drawing-block {
  margin-top: 34px;
}

.compact-heading {
  max-width: 860px;
  margin-bottom: 20px;
}

.drawing-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.drawing-grid figure {
  overflow: hidden;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
}

.drawing-grid img {
  width: 100%;
  aspect-ratio: 1.34;
  object-fit: contain;
  padding: 12px;
  background: #f7f9fb;
}

.process-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.process-grid article {
  padding: 24px;
}

.gallery-strip {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
  margin-top: 26px;
}

.gallery-strip img {
  width: 100%;
  aspect-ratio: 1.1;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--soft);
}

.cases-layout,
.quality-layout,
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 0.85fr;
  gap: 42px;
  align-items: start;
}

.quality-layout {
  grid-template-columns: 0.88fr 1.12fr;
  align-items: stretch;
}

.cases-layout > div > p,
.quality-layout > div > p {
  color: var(--muted);
  font-size: 17px;
}

.qa-list {
  display: grid;
  gap: 14px;
  margin-top: 24px;
}

.qa-list article {
  border-left: 4px solid var(--accent);
}

.faq-layout .section-heading {
  margin-bottom: 28px;
}

.faq-grid details {
  padding: 22px 24px;
}

.faq-grid summary {
  cursor: pointer;
  color: var(--deep);
  font-size: 18px;
  font-weight: 900;
}

.faq-grid summary::marker {
  color: var(--accent-dark);
}

.faq-grid p {
  margin: 14px 0 0;
}

.case-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.case-tags span {
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 8px 10px;
  color: var(--deep);
  background: var(--paper);
  font-size: 13px;
  font-weight: 700;
}

.contact-copy {
  position: sticky;
  top: 106px;
}

address {
  display: grid;
  gap: 10px;
  margin-top: 28px;
  padding: 24px;
  border-left: 4px solid var(--accent);
  background: var(--soft);
  color: var(--muted);
  font-style: normal;
}

address strong {
  color: var(--ink);
  font-size: 18px;
}

address a {
  color: var(--steel);
  font-weight: 800;
}

.lead-form {
  padding: 26px;
  box-shadow: var(--shadow);
}

.hp-field {
  position: absolute;
  left: -9999px;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.form-row {
  display: grid;
  gap: 7px;
  margin-bottom: 14px;
}

.form-row label {
  color: var(--deep);
  font-size: 14px;
  font-weight: 800;
}

.form-row input,
.form-row select,
.form-row textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 11px 12px;
  color: var(--ink);
  background: #fff;
  outline: none;
}

.form-row textarea {
  resize: vertical;
  min-height: 126px;
}

.form-row input:focus,
.form-row select:focus,
.form-row textarea:focus {
  border-color: var(--steel);
  box-shadow: 0 0 0 3px rgba(47, 111, 143, 0.16);
}

.form-row.is-invalid input,
.form-row.is-invalid select,
.form-row.is-invalid textarea {
  border-color: #c73b3b;
}

.form-status {
  min-height: 24px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.form-status.is-success {
  color: #1f7a44;
  font-weight: 800;
}

.form-status.is-error {
  color: #b12b2b;
  font-weight: 800;
}

.mailto-link {
  display: none;
  margin-top: 10px;
  color: var(--steel);
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.mailto-link.is-visible {
  display: inline-block;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  align-items: center;
  justify-content: space-between;
  padding: 28px clamp(20px, 4vw, 56px);
  color: rgba(255, 255, 255, 0.82);
  background: #111820;
}

.site-footer div {
  display: grid;
  gap: 2px;
}

.site-footer strong {
  color: var(--accent);
}

.site-footer p {
  margin: 0;
  font-size: 14px;
}

@media (max-width: 1024px) {
  h1 {
    font-size: 44px;
  }

  h2 {
    font-size: 30px;
  }

  .product-grid,
  .process-grid,
  .insight-grid,
  .solution-matrix,
  .review-grid,
  .faq-grid,
  .model-grid,
  .drawing-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .spec-block,
  .welder-feature,
  .capability-layout,
  .cases-layout,
  .quality-layout,
  .contact-layout,
  .intro-grid {
    grid-template-columns: 1fr;
  }

  .contact-copy {
    position: static;
  }
}

@media (max-width: 760px) {
  .site-header {
    min-height: 66px;
    padding: 12px 18px;
  }

  .brand-text strong {
    max-width: 220px;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 1px);
    right: 14px;
    left: 14px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--ink);
    background: #fff;
    box-shadow: var(--shadow);
  }

  .site-header.is-open .site-nav {
    display: flex;
  }

  .site-nav a {
    padding: 12px 14px;
  }

  .language-switch {
    align-self: flex-start;
    margin: 8px 6px 4px;
  }

  .language-switch a {
    padding: 7px 10px;
  }

  .hero {
    min-height: 760px;
  }

  .hero-overlay {
    background:
      linear-gradient(0deg, rgba(12, 18, 27, 0.92) 0%, rgba(12, 18, 27, 0.68) 58%, rgba(12, 18, 27, 0.22) 100%),
      linear-gradient(90deg, rgba(12, 18, 27, 0.64), rgba(12, 18, 27, 0.2));
  }

  .hero-content {
    width: min(100% - 32px, 640px);
    padding: 96px 0 30px;
  }

  h1 {
    font-size: 36px;
  }

  h2 {
    font-size: 27px;
  }

  .hero-lede,
  .section-heading p:last-child,
  .intro-grid p:last-child,
  .cases-layout > div > p {
    font-size: 16px;
  }

  .hero-actions,
  .form-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .hero-metrics {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 64px 0;
  }

  .section-inner {
    width: min(100% - 32px, 640px);
  }

  .capability-list,
  .insight-grid,
  .solution-matrix,
  .review-grid,
  .product-grid,
  .model-grid,
  .drawing-grid,
  .process-grid,
  .faq-grid,
  .form-grid {
    grid-template-columns: 1fr;
  }

  .media-panel img {
    min-height: 280px;
  }

  .welder-feature {
    padding: 20px;
  }

  .welder-photo img {
    min-height: 240px;
  }

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

  .lead-form {
    padding: 20px;
  }
}

@media (max-width: 420px) {
  .brand-mark {
    width: 46px;
    height: 34px;
    font-size: 13px;
  }

  .brand-text strong {
    max-width: 176px;
    font-size: 13px;
  }

  h1 {
    font-size: 31px;
  }

  .product-card div,
  .process-grid article,
  .capability-list article,
  .insight-grid article,
  .solution-matrix article,
  .review-grid article,
  .model-grid article,
  .qa-list article,
  .faq-grid details {
    padding: 18px;
  }
}