:root {
  color-scheme: light;
  --ink: #132033;
  --muted: #657186;
  --line: #dfe8e5;
  --paper: #f7fbf8;
  --white: #ffffff;
  --blue: #244d9a;
  --blue-dark: #182f67;
  --green: #6dbb45;
  --green-deep: #2f7d46;
  --mint: #dff3e5;
  --amber: #c99b3d;
  --shadow: 0 22px 70px rgba(24, 47, 103, 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);
  overflow-x: hidden;
}

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

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

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

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 24px;
  padding: 14px clamp(18px, 4vw, 56px);
  color: var(--white);
  transition: background 180ms ease, box-shadow 180ms ease, color 180ms ease;
}

.site-header.is-elevated {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 10px 34px rgba(19, 32, 51, 0.08);
  backdrop-filter: blur(18px);
}

.brand {
    display: inline-flex;
    align-items: center;
    width: 250px;
}

.brand img {
  width: 250px;
}

.primary-nav {
    display: flex;
    justify-content: center;
    gap: clamp(16px, 3vw, 36px);
    font-weight: bold;
    font-size: clamp(1rem, 1.5vw, 1.2rem);
}

.primary-nav a {
  opacity: 0.82;
}

.primary-nav a:hover {
  opacity: 1;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang-menu {
  position: relative;
}

.lang-toggle,
.header-cta,
.button {
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  font-weight: bold;
  line-height: 1;
}

.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-width: 96px;
  padding: 10px 13px;
  color: var(--white);
  background: transparent;
  border: 1px solid var(--green);
}

.is-elevated .lang-toggle {
  color: var(--ink);
  border-color: var(--green);
}

.lang-flag {
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  overflow: hidden;
  border-radius: 50%;
  background-color: var(--white);
  background-position: center;
  background-size: cover;
  background-repeat: no-repeat;
  font-size: 0;
  line-height: 1;
}

.lang-flag.flag-en,
[data-lang-option="en"] .lang-flag {
  background-image: url("assets/images/flag-uk.svg");
}

.lang-flag.flag-cn,
[data-lang-option="zh"] .lang-flag {
  background-image: url("assets/images/flag-cn.svg");
}

.lang-chevron {
  width: 8px;
  height: 8px;
  margin-left: auto;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: translateY(-2px) rotate(45deg);
  transition: transform 160ms ease;
}

.lang-menu.is-open .lang-chevron {
  transform: translateY(2px) rotate(225deg);
}

.lang-options {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    z-index: 40;
    display: grid;
    gap: 6px;
    min-width: 132px;
    padding: 8px;
    border: 1px solid var(--green);
    border-radius: 12px;
    background: #fff;
    box-shadow: 0 22px 54px rgba(0, 0, 0, 0.32);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-6px);
    transition: opacity 160ms ease, transform 160ms ease;
}

.lang-menu.is-open .lang-options {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.lang-option {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  min-height: 44px;
  padding: 8px 10px;
  border: 0;
  border-radius: 9px;
  background: transparent;
  cursor: pointer;
  font-weight: bold;
  text-align: left;
}

.lang-option:hover,
.lang-option.is-active {
  color: var(--white);
  background: var(--green);
}

.header-cta {
  display: inline-flex;
  padding: 13px 18px;
  color: var(--white);
  background: var(--green);
}

.hero {
  position: relative;
  min-height: 86vh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 390px);
  align-items: center;
  gap: clamp(24px, 5vw, 72px);
  padding: 116px clamp(22px, 5vw, 72px) 46px;
  overflow: hidden;
  color: var(--white);
}

.hero-media {
  position: absolute;
  inset: 0;
  overflow: hidden;
  background: #101b2a;
  transform: scale(1.02);
}

.hero-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(7, 14, 28, 0.92), rgba(15, 37, 64, 0.7), rgba(15, 37, 64, 0.18));
}

.hero-media video {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center center;
}

.hero-content,
.hero-panel {
  position: relative;
}

.hero-content {
  max-width: 820px;
  min-width: 0;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--green);
  font-size: clamp(1rem, 2vw, 1.5rem);
  font-weight: bold;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1,
.section h2,
.contact-band h2 {
  margin: 0;
  letter-spacing: 0;
  line-height: 1.02;
}

.hero h1 {
  max-width: 760px;
  font-size: clamp(3rem, 6.2vw, 6.1rem);
  overflow-wrap: break-word;
}

.hero-subtitle {
  margin: 24px 0 0;
  color: #c8eeaa;
  font-size: clamp(1.25rem, 2vw, 2rem);
  font-weight: bold;
}

.hero-copy {
  max-width: 690px;
  margin: 18px 0 0;
  color: rgba(255, 255, 255, 0.86);
  font-size: clamp(1rem, 1.5vw, 1.18rem);
  line-height: 1.75;
  overflow-wrap: anywhere;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 16px 22px;
}

.button.primary {
  color: var(--white);
  background: var(--green);
}

.button.primary:hover {
  background: var(--green-deep);
}

.button.ghost {
  color: var(--white);
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.button.dark {
  background: var(--blue-dark);
}

.hero-panel {
    align-self: end;
    min-width: 0;
    overflow: hidden;
    text-align: center;
}

.hero-panel img {
    width: 100%;
    margin-bottom: 18px;
}

.hero-panel strong {
  display: block;
  margin-bottom: 5px;
  font-size: 1.2rem;
}

.hero-panel span {
  color: rgba(255, 255, 255, 0.76);
  line-height: 1.55;
}

.signal-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
}

.signal-strip div {
  min-height: 154px;
  padding: 28px clamp(18px, 3vw, 40px);
  background: var(--white);
}

.signal-strip span,
.signal-strip small {
  display: block;
  color: var(--muted);
  font-weight: bold;
}

.signal-strip strong {
  display: block;
  margin: 12px 0 8px;
  color: var(--blue);
  font-size: clamp(2rem, 4vw, 4.2rem);
  line-height: 0.95;
}

.section {
  padding: clamp(72px, 9vw, 126px) clamp(22px, 5vw, 72px);
}

.section-heading {
  max-width: 920px;
  margin-bottom: clamp(32px, 5vw, 58px);
}

.section-heading.compact {
  max-width: 920px;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.section h2,
.contact-band h2 {
  font-size: clamp(2.35rem, 5vw, 5.2rem);
}

.section-heading p:not(.eyebrow),
.authority-copy p:not(.eyebrow) {
  color: var(--muted);
  font-size: 1.06rem;
  line-height: 1.78;
}

.exposure-tool {
  display: grid;
  grid-template-columns: 0.75fr 1fr;
  gap: 36px;
  align-items: stretch;
  padding: clamp(24px, 4vw, 48px);
  border-radius: 8px;
  background: var(--white);
  box-shadow: var(--shadow);
}

.tool-copy h3,
.journey-detail h3,
.service-card h3 {
  margin: 0;
  font-size: clamp(1.45rem, 2.5vw, 2.25rem);
  line-height: 1.1;
}

.tool-copy p,
.service-card p,
.journey-detail p,
.journey-detail li {
  color: var(--muted);
  line-height: 1.65;
}

.calculator {
  display: grid;
  align-content: center;
  gap: 18px;
}

.calculator label {
  color: var(--blue-dark);
  font-weight: bold;
}

.calc-inputs {
  display: grid;
  grid-template-columns: 1fr 180px;
  gap: 16px;
  align-items: center;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--green);
}

input[type="number"] {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: var(--paper);
}

.calc-result {
  padding: 20px;
  border-left: 5px solid var(--green);
  background: #f1f8f2;
}

.calc-result span {
  display: block;
  color: var(--muted);
  font-weight: bold;
}

.calc-result strong {
  display: block;
  margin-top: 8px;
  color: var(--blue-dark);
  font-size: clamp(1.35rem, 2.4vw, 2.3rem);
}

.journey {
  background: var(--white);
}

.journey-layout {
  display: grid;
  grid-template-columns: 330px 1fr;
  gap: 30px;
  align-items: stretch;
}

.journey-tabs {
  display: grid;
  gap: 12px;
}

.journey-tab {
  display: grid;
  grid-template-columns: 58px 1fr;
  align-items: center;
  gap: 14px;
  min-height: 92px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: var(--paper);
  text-align: left;
  cursor: pointer;
}

.journey-tab strong {
    font-size: clamp(1.2rem, 2vw, 1.4rem);
}

.journey-tab span {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  color: var(--blue);
  background: var(--mint);
  font-weight: bold;
}

.journey-tab.is-active {
  color: var(--white);
  background: var(--blue-dark);
  border-color: var(--blue-dark);
}

.journey-tab.is-active span {
  color: var(--ink);
  background: var(--green);
}

.journey-detail {
  display: grid;
  grid-template-columns: minmax(50px, 0.1fr) 1fr;
  gap: 30px;
  align-items: center;
  min-height: 420px;
  padding: clamp(20px, 4vw, 46px);
  border-radius: 8px;
  background: #eef7f7;
}

.journey-detail img {
  width: 100%;
}

.standard {
  display: inline-flex;
  margin-bottom: 16px;
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--blue-dark);
  background: rgba(109, 187, 69, 0.24);
  font-weight: bold;
}

.journey-detail ul {
  display: grid;
  gap: 8px;
  margin: 16px 0 0;
  padding-left: 20px;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.service-card {
  min-height: 270px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.service-card:hover {
  transform: translateY(-6px);
  border-color: rgba(109, 187, 69, 0.55);
  box-shadow: var(--shadow);
}

.service-card img {
    width: 100%;
    height: auto;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    border-radius: 1em;
    margin-bottom: 1em;
}

.service-card span {
    z-index: 0;
    color: var(--paper);
    font-weight: bold;
    position: absolute;
    padding: 0.5em;
    aspect-ratio: 1 / 1;
    background-color: var(--green-deep);
    border-radius: 50%;
    width: 3em;
    text-align: center;
    align-items: center;
    display: inline-grid;
}

.service-card span:before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    left: -2em;
    right: 50%;
    background-color: var(--green-deep);
    z-index: -1;
}

.standards {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 34px;
}

.standards span {
  padding: 11px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--blue-dark);
  background: var(--white);
  font-weight: bold;
}

.authority {
  display: grid;
  grid-template-columns: minmax(280px, 420px) minmax(0, 1fr);
  gap: clamp(32px, 6vw, 82px);
  align-items: center;
  background: #101b2a;
  color: var(--white);
}

.authority-image {
  overflow: hidden;
  border-radius: 8px;
  background: #223047;
}

.authority-image img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.authority-copy h2 {
  margin: 0;
  font-size: clamp(2.25rem, 4.5vw, 4.8rem);
  line-height: 1.04;
}

.authority-copy p:not(.eyebrow) {
  color: rgba(255, 255, 255, 0.76);
}

.authority-points {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 28px;
}

.authority-points span {
    padding: 12px 14px;
    border-radius: 999px;
    color: var(--ink);
    font-weight: bold;
    background-color: #d9f2cf;
}

.contact-band {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(320px, 0.95fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: start;
  padding: clamp(64px, 8vw, 110px) clamp(22px, 5vw, 72px);
  color: var(--ink);
  background: radial-gradient(circle at 10% 10%, rgba(255, 255, 255, 1), transparent 70%), linear-gradient(135deg, var(--green), #b9e86e);
}

.contact-band .eyebrow {
  color: var(--blue-dark);
}

.contact-copy p:not(.eyebrow) {
  max-width: 680px;
  color: rgba(19, 32, 51, 0.78);
  font-size: 1.05rem;
  line-height: 1.75;
}

.contact-points {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 28px;
}

.contact-points span {
  padding: 10px 13px;
  border-radius: 999px;
  color: var(--white);
  background: rgba(16, 27, 42, 0.86);
  font-weight: bold;
}

.contact-form {
  display: grid;
  gap: 18px;
  padding: clamp(22px, 3vw, 34px);
  border: 1px solid rgba(255, 255, 255, 0.52);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: 0 24px 70px rgba(19, 32, 51, 0.18);
  backdrop-filter: blur(14px);
}

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

.contact-form label {
  display: grid;
  gap: 8px;
  color: var(--blue-dark);
  font-size: 0.9rem;
  font-weight: bold;
}

.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  border: 1px solid rgba(19, 32, 51, 0.13);
  border-radius: 8px;
  color: var(--ink);
  background: var(--white);
  outline: none;
}

.contact-form input,
.contact-form select {
  min-height: 48px;
  padding: 0 14px;
}

.contact-form textarea {
  min-height: 132px;
  padding: 14px;
  resize: vertical;
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 4px rgba(36, 77, 154, 0.12);
}

.contact-form .button {
  justify-self: start;
  min-width: 190px;
}

.site-footer {
  padding: clamp(48px, 7vw, 86px) clamp(22px, 5vw, 72px) 28px;
  color: rgba(255, 255, 255, 0.78);
  background: #101b2a;
}

.footer-brand {
  display: grid;
  grid-template-columns: 200px minmax(0, 620px);
  gap: 24px;
  align-items: center;
  padding-bottom: 42px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-brand img {
  width: 200px;
}

.footer-brand p {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.7;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  padding: 38px 0;
}

.footer-links div {
  display: grid;
  align-content: start;
  gap: 12px;
}

.footer-links h2 {
  margin: 0 0 8px;
  color: var(--white);
  font-size: 1rem;
}

.footer-links a,
.footer-links span {
  color: rgba(255, 255, 255, 0.72);
}

.footer-links a:hover {
  color: var(--green);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.58);
  font-size: 0.92rem;
}

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

  .primary-nav {
    display: none;
  }

  .hero,
  .signal-strip,
  .exposure-tool,
  .journey-layout,
  .journey-detail,
  .service-grid,
  .authority,
  .contact-band {
    grid-template-columns: 1fr;
  }

  .footer-brand,
  .footer-links {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding-top: 118px;
  }

  .hero-panel {
    max-width: 430px;
  }

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

@media (max-width: 640px) {
  .site-header {
    padding: 10px 14px;
  }

  .brand {
    width: 220px;
  }

  .brand img {
    width: 220px;
    height: auto;
  }

  .header-cta {
    display: none;
  }

  .hero {
    padding: 96px 18px 44px;
    justify-items: start;
  }

  .hero-content,
  .hero-panel {
    width: min(330px, 100%);
    max-width: min(330px, 100%);
  }

  .hero h1 {
    max-width: 330px;
    width: 100%;
    font-size: 1.96rem;
  }

  .eyebrow,
  .hero-copy {
    max-width: 330px;
  }

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

  .button {
    width: 100%;
  }

  .signal-strip {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 64px 18px;
  }

  .calc-inputs {
    grid-template-columns: 1fr;
  }

  .field-pair {
    grid-template-columns: 1fr;
  }

  .contact-form .button {
    width: 100%;
  }

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

  .journey-tab {
    min-height: 78px;
  }
}