:root {
  --ink: #17221f;
  --muted: #65706c;
  --paper: #f7f4ed;
  --canvas: #ebe6dc;
  --pine: #18362f;
  --moss: #496a4d;
  --copper: #b66f42;
  --gold: #d6a85f;
  --white: #ffffff;
  --line: rgba(23, 34, 31, 0.14);
  --shadow: 0 24px 70px rgba(23, 34, 31, 0.16);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
}

body.lang-zh {
  font-family: "Microsoft YaHei", "PingFang SC", Inter, ui-sans-serif, system-ui, sans-serif;
}

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

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

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: grid;
  grid-template-columns: minmax(180px, 1fr) auto minmax(150px, 1fr);
  align-items: center;
  gap: 24px;
  padding: 18px clamp(18px, 4vw, 64px);
  color: var(--white);
  background: linear-gradient(180deg, rgba(12, 24, 22, 0.72), rgba(12, 24, 22, 0.12));
  backdrop-filter: blur(14px);
}

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

.brand-mark {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.46);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.12);
  font-weight: 800;
}

.brand strong,
.brand small {
  display: block;
  line-height: 1.15;
}

.brand small {
  margin-top: 3px;
  color: rgba(255, 255, 255, 0.72);
  font-size: 12px;
}

.main-nav {
  display: flex;
  justify-content: center;
  gap: clamp(18px, 3vw, 40px);
  font-size: 14px;
  color: rgba(255, 255, 255, 0.82);
}

.main-nav a {
  position: relative;
  padding: 8px 0;
}

.main-nav a::after {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 1px;
  content: "";
  transform: scaleX(0);
  transform-origin: left;
  background: var(--gold);
  transition: transform 180ms ease;
}

.main-nav a:hover::after {
  transform: scaleX(1);
}

.language-toggle {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: 1px solid rgba(255, 255, 255, 0.34);
  border-radius: 999px;
  padding: 8px 11px;
  color: var(--white);
  background: rgba(255, 255, 255, 0.12);
  cursor: pointer;
}

.toggle-track {
  position: relative;
  width: 38px;
  height: 20px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.24);
}

.toggle-track span {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--gold);
  transition: transform 180ms ease;
}

body.lang-zh .toggle-track span {
  transform: translateX(18px);
}

.hero {
  position: relative;
  min-height: 92vh;
  overflow: hidden;
  color: var(--white);
  background: #10251f;
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(10, 21, 19, 0.78) 0%, rgba(10, 21, 19, 0.44) 47%, rgba(10, 21, 19, 0.2) 100%),
    linear-gradient(180deg, rgba(10, 21, 19, 0.34), rgba(10, 21, 19, 0.08) 68%, rgba(10, 21, 19, 0.62));
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(760px, calc(100% - 36px));
  padding: clamp(150px, 22vh, 230px) 0 150px clamp(18px, 8vw, 116px);
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--copper);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

body.lang-zh .eyebrow {
  letter-spacing: 0.08em;
}

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

h1 {
  margin-bottom: 22px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(58px, 8vw, 118px);
  line-height: 0.92;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0;
  max-width: 780px;
  font-size: clamp(34px, 5vw, 64px);
  line-height: 1.02;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  font-size: 20px;
  line-height: 1.18;
}

.hero-copy {
  max-width: 610px;
  color: rgba(255, 255, 255, 0.82);
  font-size: clamp(18px, 2vw, 24px);
  line-height: 1.55;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: 6px;
  padding: 0 22px;
  font-weight: 800;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button.primary {
  color: #18231f;
  background: var(--gold);
}

.button.ghost {
  border-color: rgba(255, 255, 255, 0.36);
  color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.hero-panel {
  position: absolute;
  z-index: 2;
  right: clamp(18px, 5vw, 78px);
  bottom: clamp(28px, 7vw, 74px);
  display: grid;
  width: min(440px, calc(100% - 36px));
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(12, 24, 22, 0.58);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.22);
  backdrop-filter: blur(18px);
}

.hero-panel div {
  padding: 18px;
  border-right: 1px solid rgba(255, 255, 255, 0.14);
}

.hero-panel div:last-child {
  border-right: 0;
}

.hero-panel strong {
  display: block;
  margin-bottom: 6px;
  color: var(--gold);
  font-size: 30px;
}

.hero-panel span {
  color: rgba(255, 255, 255, 0.72);
  font-size: 12px;
  line-height: 1.35;
}

section {
  padding: clamp(76px, 10vw, 128px) clamp(18px, 6vw, 88px);
}

.band {
  background: var(--canvas);
}

.intro {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 520px);
  gap: clamp(28px, 5vw, 80px);
  align-items: end;
}

.intro p:last-child,
.contact p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.8;
}

.section-heading {
  margin-bottom: clamp(34px, 5vw, 58px);
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.product-card {
  min-height: 300px;
  padding: 28px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.86), rgba(255, 255, 255, 0.58)),
    var(--paper);
}

.product-icon {
  display: inline-grid;
  width: 44px;
  height: 44px;
  place-items: center;
  margin-bottom: 88px;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--moss);
  font-size: 13px;
  font-weight: 900;
}

.product-card p,
.timeline p,
.advantage-item p {
  color: var(--muted);
  line-height: 1.65;
}

.advantages {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 1.15fr);
  gap: clamp(32px, 6vw, 96px);
}

.advantage-list {
  display: grid;
  gap: 24px;
}

.advantage-item {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 18px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.advantage-item span {
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background:
    linear-gradient(135deg, rgba(214, 168, 95, 0.9), rgba(73, 106, 77, 0.72)),
    var(--gold);
}

.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.timeline li {
  min-height: 250px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 26px;
  background: rgba(255, 255, 255, 0.42);
  box-shadow: 0 18px 40px rgba(23, 34, 31, 0.07);
}

.timeline span {
  display: block;
  margin-bottom: 64px;
  color: var(--copper);
  font-weight: 900;
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 520px);
  gap: clamp(32px, 7vw, 110px);
  align-items: start;
}

.contact-form {
  display: grid;
  gap: 16px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.55);
  box-shadow: var(--shadow);
}

label {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

input,
textarea {
  width: 100%;
  border: 1px solid rgba(23, 34, 31, 0.18);
  border-radius: 6px;
  padding: 13px 14px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.8);
  font: inherit;
}

input:focus,
textarea:focus {
  outline: 2px solid rgba(214, 168, 95, 0.42);
  border-color: var(--gold);
}

.form-notice {
  min-height: 22px;
  margin: 0;
  color: var(--moss);
  font-size: 14px;
  font-weight: 800;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 26px clamp(18px, 6vw, 88px);
  color: rgba(255, 255, 255, 0.72);
  background: var(--pine);
  font-size: 14px;
}

@media (max-width: 980px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .main-nav {
    display: none;
  }

  .hero-content {
    padding-left: 24px;
  }

  .hero-panel,
  .intro,
  .advantages,
  .contact {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 640px) {
  .site-header {
    padding: 14px 16px;
  }

  .brand small {
    display: none;
  }

  .hero {
    min-height: 860px;
  }

  .hero-content {
    width: calc(100% - 32px);
    padding: 132px 0 0 16px;
  }

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

  .hero-panel div {
    border-right: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  }

  .hero-panel div:last-child {
    border-bottom: 0;
  }

  .product-grid,
  .timeline {
    grid-template-columns: 1fr;
  }

  .product-card {
    min-height: 230px;
  }

  .product-icon,
  .timeline span {
    margin-bottom: 36px;
  }

  .site-footer {
    flex-direction: column;
  }
}