:root {
  --orange: #ff7f16;
  --orange-dark: #df6100;
  --ink: #1f252b;
  --muted: #6f747a;
  --line: #e8e2dc;
  --soft: #f7f4ef;
  --white: #fff;
  --shadow: 0 18px 45px rgba(31, 37, 43, .12);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  background: var(--white);
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 16px clamp(20px, 5vw, 72px);
  background: rgba(255,255,255,.92);
  border-bottom: 1px solid rgba(232,226,220,.8);
  backdrop-filter: blur(14px);
}
.brand { display: flex; align-items: baseline; gap: 8px; margin-right: auto; font-weight: 800; }
.brand-mark { color: var(--orange); font-size: 28px; letter-spacing: .5px; }
.brand-name { color: #333; font-size: 18px; }
.nav { display: flex; gap: 22px; color: #4d5257; font-size: 15px; }
.nav a:hover, .header-call:hover { color: var(--orange); }
.header-call {
  padding: 8px 14px;
  color: var(--orange-dark);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-weight: 700;
}

.hero {
  position: relative;
  min-height: 760px;
  display: grid;
  align-items: end;
  padding: 120px clamp(20px, 6vw, 92px) 56px;
  overflow: hidden;
  color: var(--white);
  background: #222;
}
.hero-media {
  position: absolute;
  inset: 0;
}
.hero-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(15,18,20,.86), rgba(15,18,20,.48) 48%, rgba(15,18,20,.15)), linear-gradient(0deg, rgba(15,18,20,.78), transparent 46%);
}
.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center bottom;
}
.hero-content {
  position: relative;
  max-width: 920px;
}
.eyebrow {
  margin: 0 0 12px;
  color: var(--orange);
  font-weight: 800;
  letter-spacing: .04em;
  text-transform: uppercase;
}
.hero h1 {
  margin: 0;
  max-width: 880px;
  font-size: clamp(42px, 6vw, 82px);
  line-height: 1.05;
  letter-spacing: 0;
}
.hero-copy {
  max-width: 760px;
  margin: 24px 0 0;
  color: rgba(255,255,255,.88);
  font-size: 20px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-weight: 800;
  cursor: pointer;
}
.btn.primary { color: #fff; background: var(--orange); }
.btn.primary:hover { background: var(--orange-dark); }
.btn.ghost { color: #fff; border-color: rgba(255,255,255,.45); background: rgba(255,255,255,.08); }
.btn.ghost:hover { border-color: var(--orange); color: var(--orange); }
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(120px, 1fr));
  gap: 12px;
  max-width: 860px;
  margin: 44px 0 0;
}
.hero-stats div {
  padding: 18px;
  border: 1px solid rgba(255,255,255,.22);
  background: rgba(255,255,255,.08);
  backdrop-filter: blur(8px);
  border-radius: 8px;
}
.hero-stats dt { color: var(--orange); font-size: 36px; font-weight: 900; line-height: 1; }
.hero-stats dd { margin: 8px 0 0; color: rgba(255,255,255,.82); font-size: 14px; }

.case-hero {
  padding: 118px clamp(20px, 6vw, 92px) 70px;
  color: #fff;
  background: linear-gradient(90deg, rgba(17,20,24,.9), rgba(17,20,24,.5)), url("assets/hero-factory.jpg") center / cover;
}
.case-hero h1 {
  max-width: 780px;
  margin: 0;
  font-size: clamp(42px, 6vw, 76px);
  line-height: 1.08;
}
.case-hero p:not(.eyebrow) {
  max-width: 760px;
  margin: 20px 0 0;
  color: rgba(255,255,255,.84);
  font-size: 19px;
}
.btn.ghost.dark {
  color: #fff;
  border-color: rgba(255,255,255,.45);
}

.section { padding: 88px clamp(20px, 6vw, 92px); }
.section-head {
  max-width: 780px;
  margin-bottom: 32px;
}
.section-head h2, .factory-copy h2, .quote h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1.14;
}
.section-head p:not(.eyebrow), .factory-copy p, .quote p {
  color: var(--muted);
  font-size: 17px;
}
.trust, .quote, .faq { background: var(--soft); }
.feature-grid, .service-list {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.feature-grid article, .service-list article {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}
.feature-grid span { color: var(--orange); font-size: 28px; font-weight: 900; }
h3 { margin: 10px 0 8px; font-size: 22px; line-height: 1.28; }
.feature-grid p, .service-list p, .case-card p { margin: 0; color: var(--muted); }

.performance-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr 1fr;
  gap: 18px;
}
.performance-card {
  position: relative;
  min-height: 310px;
  overflow: hidden;
  border-radius: 8px;
  background: #111418;
  color: #fff;
}
.performance-card.large {
  grid-row: span 2;
  min-height: 638px;
}
.performance-card img {
  width: 100%;
  height: 100%;
  position: absolute;
  inset: 0;
  object-fit: cover;
  object-position: center 72%;
  opacity: .78;
  transition: transform .4s ease;
}
.performance-card::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(17,20,24,.08), rgba(17,20,24,.84));
}
.performance-card:hover img { transform: scale(1.04); }
.performance-card div {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
  padding: 24px;
}
.performance-card span {
  color: var(--orange);
  font-weight: 900;
  letter-spacing: .08em;
}
.performance-card h3 { font-size: 28px; }
.performance-card p { margin: 0; color: rgba(255,255,255,.82); }

.culture-section {
  color: #fff;
  background: var(--orange);
}
.culture-section .eyebrow { color: #fff; }
.culture-section .section-head p:not(.eyebrow) { color: rgba(255,255,255,.84); }
.culture-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.culture-grid article {
  min-height: 180px;
  padding: 26px;
  border: 1px solid rgba(255,255,255,.24);
  border-radius: 8px;
  background: rgba(255,255,255,.1);
}
.culture-grid span {
  display: inline-block;
  margin-bottom: 18px;
  color: rgba(255,255,255,.76);
  font-weight: 900;
}
.culture-grid h3 {
  margin: 0;
  color: #fff;
  font-size: 26px;
}

.catalog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.catalog-grid article {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 8px 24px rgba(31,37,43,.06);
}
.catalog-grid img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  object-position: center 72%;
  background: #f5f5f5;
}
.catalog-grid div { padding: 20px; }
.catalog-grid span {
  color: var(--orange);
  font-weight: 900;
}
.catalog-grid h3 { margin-top: 8px; }
.catalog-grid p { margin: 0; color: var(--muted); }
.wechat-card.big {
  grid-template-columns: 180px 1fr;
  align-self: start;
}
.wechat-card.big img {
  width: 180px;
  height: 180px;
}

.factory {
  display: grid;
  grid-template-columns: .85fr 1.15fr;
  gap: 46px;
  align-items: center;
}
.check-list {
  padding: 0;
  margin: 24px 0 0;
  list-style: none;
}
.check-list li {
  padding: 12px 0 12px 30px;
  border-bottom: 1px solid var(--line);
  position: relative;
}
.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 20px;
  width: 10px;
  height: 10px;
  background: var(--orange);
  border-radius: 50%;
}
.factory-images {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}
.factory-images img {
  height: 420px;
  width: 100%;
  object-fit: cover;
  object-position: center bottom;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.quote {
  display: grid;
  grid-template-columns: .9fr 1fr;
  gap: 46px;
  align-items: start;
}
.quote-form {
  display: grid;
  gap: 14px;
  padding: 28px;
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}
label {
  display: grid;
  gap: 7px;
  font-weight: 800;
}
input, textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 6px;
  font: inherit;
  outline: none;
}
input:focus, textarea:focus { border-color: var(--orange); box-shadow: 0 0 0 3px rgba(255,127,22,.13); }
.form-note { margin: 0; color: var(--muted); }
.form-note a { color: var(--orange-dark); font-weight: 800; }
.wechat-card {
  display: grid;
  grid-template-columns: 112px 1fr;
  gap: 16px;
  align-items: center;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--soft);
}
.wechat-card img {
  width: 112px;
  height: 112px;
  object-fit: cover;
  border-radius: 6px;
  background: #fff;
}
.wechat-card strong { font-size: 18px; }
.wechat-card p { margin: 4px 0 0; color: var(--muted); font-size: 14px; }

.ai-section { background: #16191d; color: #fff; }
.ai-section .section-head p:not(.eyebrow) { color: rgba(255,255,255,.72); }
.ai-panel {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 14px;
  max-width: 980px;
  padding: 22px;
  border: 1px solid rgba(255,255,255,.14);
  border-radius: 8px;
  background: rgba(255,255,255,.06);
}
.chat-area { display: grid; gap: 14px; }
.chat-window {
  display: grid;
  gap: 12px;
  min-height: 220px;
  max-height: 380px;
  overflow: auto;
  padding: 16px;
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
}
.message {
  max-width: 78%;
  padding: 12px 14px;
  border-radius: 8px;
}
.message.bot { justify-self: start; background: var(--soft); }
.message.user { justify-self: end; color: #fff; background: var(--orange); }
.chat-form { display: grid; grid-template-columns: 1fr auto; gap: 10px; }
.quick-questions { display: flex; flex-wrap: wrap; gap: 10px; }
.quick-questions button {
  padding: 8px 12px;
  border: 1px solid rgba(255,255,255,.28);
  border-radius: 999px;
  color: #fff;
  background: transparent;
  cursor: pointer;
}
.quick-questions button:hover { border-color: var(--orange); color: var(--orange); }
.ai-wechat {
  align-self: stretch;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 10px;
  padding: 18px;
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
}
.ai-wechat img {
  width: 100%;
  border-radius: 8px;
  border: 1px solid var(--line);
}
.ai-wechat strong { font-size: 20px; }
.ai-wechat p { margin: 0; color: var(--muted); font-size: 14px; }

.faq details {
  max-width: 980px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}
.faq summary {
  cursor: pointer;
  font-size: 20px;
  font-weight: 800;
}
.faq p { color: var(--muted); margin-bottom: 0; }

.site-footer {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 24px;
  padding: 48px clamp(20px, 6vw, 92px) 78px;
  color: rgba(255,255,255,.78);
  background: #111418;
}
.site-footer strong { color: #fff; font-size: 24px; }
.site-footer a { color: var(--orange); font-weight: 800; }
.site-footer p { margin: 6px 0; }

.mobile-cta {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 25;
  display: none;
  grid-template-columns: repeat(3, 1fr);
  background: #fff;
  box-shadow: 0 -8px 20px rgba(0,0,0,.12);
}
.mobile-cta a {
  padding: 12px 8px;
  text-align: center;
  font-weight: 800;
  border-right: 1px solid var(--line);
}
.mobile-cta a:first-child { color: #fff; background: var(--orange); }

@media (max-width: 1100px) {
  .feature-grid, .culture-grid { grid-template-columns: repeat(2, 1fr); }
  .performance-grid { grid-template-columns: 1fr 1fr; }
  .catalog-grid { grid-template-columns: repeat(2, 1fr); }
  .performance-card.large { grid-row: span 1; min-height: 360px; }
  .factory, .quote { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .site-header { padding: 12px 16px; }
  .brand-mark { font-size: 23px; }
  .brand-name { font-size: 16px; }
  .nav, .header-call { display: none; }
  .hero {
    min-height: 700px;
    padding: 88px 18px 36px;
  }
  .hero h1 { font-size: 40px; }
  .hero-copy { font-size: 17px; }
  .hero-stats, .feature-grid, .performance-grid, .culture-grid, .catalog-grid, .factory-images {
    grid-template-columns: 1fr;
  }
  .performance-card, .performance-card.large { min-height: 320px; }
  .section { padding: 64px 18px; }
  .factory-images img { height: 300px; }
  .chat-form { grid-template-columns: 1fr; }
  .ai-panel { grid-template-columns: 1fr; }
  .ai-wechat img { max-width: 220px; }
  .message { max-width: 92%; }
  .wechat-card { grid-template-columns: 92px 1fr; }
  .wechat-card img { width: 92px; height: 92px; }
  .wechat-card.big { grid-template-columns: 1fr; }
  .wechat-card.big img { width: 180px; height: 180px; }
  .site-footer { grid-template-columns: 1fr; padding-bottom: 86px; }
  .mobile-cta { display: grid; }
}