:root {
  color-scheme: light;
  --bg: #f4f7f8;
  --surface: #ffffff;
  --surface-soft: #edf4f4;
  --ink: #132325;
  --muted: #607174;
  --line: #d9e4e4;
  --teal: #08756f;
  --teal-dark: #064d4a;
  --coral: #e76f5f;
  --graphite: #253133;
  --shadow: 0 20px 60px rgba(12, 28, 31, 0.22);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--bg);
  letter-spacing: 0;
}

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

.lang-zh,
.lang-en {
  display: inline;
}

.lang-line {
  display: block;
}

body[data-lang="zh"] .lang-en {
  display: none !important;
}

body[data-lang="en"] .lang-zh {
  display: none !important;
}

button,
input {
  font: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 76px;
  padding: 12px clamp(18px, 4vw, 56px);
  color: var(--ink);
  background: rgba(255, 255, 255, 0.9);
  border-bottom: 1px solid rgba(217, 228, 228, 0.9);
  backdrop-filter: blur(12px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  padding: 8px 0;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 34px;
  height: 34px;
  color: var(--teal-dark);
  background: transparent;
  border: 1px solid rgba(8, 117, 111, 0.28);
  border-radius: 7px;
  font-size: 13px;
}

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

.brand-name {
  color: var(--ink);
  font-size: 14px;
  font-weight: 800;
  line-height: 1.1;
  white-space: nowrap;
}

.brand-subtitle {
  color: var(--muted);
  font-size: 11px;
  line-height: 1.2;
}

.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  min-width: 0;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 0;
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
  background: transparent;
  border: 0;
  border-radius: 0;
  box-shadow: none;
}

.site-nav a {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 36px;
  padding: 0;
  border-radius: 0;
  font-weight: 700;
  transition:
    color 0.2s ease,
    opacity 0.2s ease;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 2px;
  left: 0;
  height: 1px;
  background: currentColor;
  content: "";
  opacity: 0;
  transform: scaleX(0.4);
  transition:
    opacity 0.2s ease,
    transform 0.2s ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--teal-dark);
}

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  opacity: 0.7;
  transform: scaleX(1);
}

.site-nav .nav-cta {
  color: var(--teal-dark);
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 0;
  padding: 0;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 7px;
  box-shadow: none;
  overflow: hidden;
}

.lang-button {
  min-width: 46px;
  min-height: 32px;
  padding: 5px 10px;
  color: var(--muted);
  background: transparent;
  border: 0;
  border-radius: 0;
  cursor: pointer;
  font-size: 12px;
  font-weight: 800;
}

.lang-button + .lang-button {
  border-left: 1px solid var(--line);
}

.lang-button.is-active {
  color: var(--teal-dark);
  background: var(--surface-soft);
}

.order-hero {
  position: relative;
  min-height: calc(100vh - 72px);
  overflow: hidden;
  color: #fff;
}

.hero-bg,
.hero-shade {
  position: absolute;
  inset: 0;
}

.hero-bg {
  background-image: url("assets/domain-hero.png");
  background-position: center;
  background-size: cover;
  transform: scale(1.02);
}

.hero-shade {
  background:
    linear-gradient(90deg, rgba(5, 18, 21, 0.82) 0%, rgba(5, 18, 21, 0.58) 42%, rgba(5, 18, 21, 0.2) 100%),
    linear-gradient(180deg, rgba(5, 18, 21, 0.2) 0%, rgba(5, 18, 21, 0.62) 100%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(340px, 430px);
  align-items: center;
  gap: clamp(32px, 5vw, 72px);
  width: min(1180px, calc(100% - 36px));
  min-height: calc(100vh - 72px);
  margin: 0 auto;
  padding: 56px 0;
}

.hero-copy {
  max-width: 650px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--coral);
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
}

.hero-copy h1 {
  margin: 0;
  font-size: clamp(44px, 7vw, 82px);
  line-height: 1.02;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 560px;
  margin: 22px 0 0;
  color: rgba(255, 255, 255, 0.84);
  font-size: clamp(17px, 2vw, 22px);
  line-height: 1.7;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 30px;
}

.hero-badges span {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 8px 12px;
  color: #eaf7f7;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 8px;
  font-size: 14px;
  backdrop-filter: blur(10px);
}

.calculator {
  width: 100%;
  padding: 26px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.96);
  border: 1px solid rgba(255, 255, 255, 0.55);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.panel-heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 24px;
}

.panel-heading p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.panel-heading strong {
  color: var(--teal-dark);
  font-size: 20px;
  text-align: right;
}

.field-label {
  display: block;
  margin-bottom: 10px;
  color: var(--graphite);
  font-size: 14px;
  font-weight: 700;
}

.quantity-control {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr) 52px;
  height: 56px;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: var(--surface);
}

.step-button {
  display: grid;
  place-items: center;
  width: 52px;
  height: 54px;
  color: var(--teal-dark);
  background: var(--surface-soft);
  border: 0;
  cursor: pointer;
  font-size: 24px;
  line-height: 1;
}

.step-button:hover,
.step-button:focus-visible {
  color: #fff;
  background: var(--teal);
}

#quantityInput {
  width: 100%;
  height: 54px;
  padding: 0 12px;
  color: var(--ink);
  background: #fff;
  border: 0;
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
  outline: 0;
  text-align: center;
  font-size: 22px;
  font-weight: 800;
}

#quantityInput:focus {
  box-shadow: inset 0 0 0 2px rgba(8, 117, 111, 0.24);
}

.helper-text {
  min-height: 22px;
  margin: 10px 0 20px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.helper-text.is-error {
  color: #b33a2e;
}

.quote-list {
  display: grid;
  gap: 10px;
  margin: 0 0 22px;
}

.quote-list div {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 48px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.quote-list dt {
  color: var(--muted);
  font-size: 14px;
}

.quote-list dd {
  margin: 0;
  color: var(--ink);
  font-size: 18px;
  font-weight: 800;
  text-align: right;
}

#quantityDisplay {
  font-size: 16px;
  line-height: 1.35;
}

.quote-list div:last-child dd {
  color: var(--teal-dark);
  font-size: 26px;
}

.order-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  min-height: 54px;
  padding: 12px 18px;
  color: #fff;
  background: var(--teal);
  border: 0;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 800;
}

.order-button:hover,
.order-button:focus-visible {
  background: var(--teal-dark);
}

.order-button:disabled {
  cursor: not-allowed;
  background: #93a7a8;
}

.form-note {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.5;
  text-align: center;
}

.pricing-section {
  background: var(--bg);
}

.section-inner {
  width: min(1180px, calc(100% - 36px));
  margin: 0 auto;
  padding: 70px 0 78px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 24px;
}

.section-heading h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.16;
}

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

.price-card {
  min-height: 178px;
  padding: 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.price-card.is-active {
  border-color: rgba(8, 117, 111, 0.75);
  box-shadow: 0 12px 32px rgba(8, 117, 111, 0.14);
}

.tier-range {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 5px 10px;
  color: var(--teal-dark);
  background: var(--surface-soft);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 800;
}

.price-card strong {
  display: block;
  margin-top: 18px;
  color: var(--ink);
  font-size: 36px;
  line-height: 1;
}

.price-card p {
  margin: 12px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.limit-strip {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 18px;
  padding: 16px 18px;
  color: var(--graphite);
  background: #fff8f6;
  border: 1px solid rgba(231, 111, 95, 0.28);
  border-radius: 8px;
}

.limit-strip strong {
  color: #a74438;
  white-space: nowrap;
}

.limit-strip span {
  color: var(--muted);
  line-height: 1.5;
}

.faq-section {
  background: #fff;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.faq-item summary {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 62px;
  padding: 18px 56px 18px 20px;
  color: var(--ink);
  cursor: pointer;
  font-weight: 800;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  position: absolute;
  right: 20px;
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  color: var(--teal-dark);
  background: var(--surface-soft);
  border-radius: 8px;
  content: "+";
  font-size: 20px;
  line-height: 1;
}

.faq-item[open] {
  border-color: rgba(8, 117, 111, 0.42);
}

.faq-item[open] summary::after {
  color: #fff;
  background: var(--teal);
  content: "-";
}

.faq-answer {
  padding: 0 20px 20px;
  color: var(--muted);
  line-height: 1.7;
}

.faq-answer p {
  margin: 0;
}

.faq-answer p + p {
  margin-top: 10px;
}

.faq-answer ul {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.faq-answer li {
  padding: 10px 12px;
  color: var(--graphite);
  background: var(--surface-soft);
  border-radius: 8px;
  font-weight: 700;
  line-height: 1.45;
  text-align: center;
}

.faq-answer a {
  color: var(--teal-dark);
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 24px clamp(18px, 4vw, 56px);
  color: rgba(255, 255, 255, 0.76);
  background: var(--graphite);
}

.site-footer a {
  color: #fff;
}

@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: 1fr;
    align-items: start;
    padding: 42px 0;
  }

  .hero-copy {
    max-width: 720px;
  }

  .calculator {
    max-width: 560px;
  }

  .pricing-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 640px) {
  .site-header {
    position: static;
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
    min-height: auto;
  }

  .brand {
    width: 100%;
  }

  .header-actions {
    width: 100%;
    align-items: stretch;
    flex-direction: column;
    gap: 10px;
  }

  .site-nav {
    width: 100%;
    justify-content: space-between;
    gap: 16px;
    padding: 0;
    overflow-x: auto;
  }

  .lang-switch {
    align-self: flex-start;
  }

  .order-hero,
  .hero-inner {
    min-height: auto;
  }

  .hero-inner,
  .section-inner {
    width: min(100% - 28px, 1180px);
  }

  .hero-copy h1 {
    font-size: 44px;
  }

  .calculator {
    padding: 20px;
  }

  .panel-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 6px;
  }

  .panel-heading strong {
    text-align: left;
  }

  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 8px;
  }

  .limit-strip,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .faq-answer ul {
    grid-template-columns: 1fr;
  }
}