:root {
  color-scheme: light;
  --ink: #18212b;
  --muted: #5b6672;
  --surface: #ffffff;
  --surface-soft: #f4f7f8;
  --line: #d7dfe3;
  --brand: #245746;
  --brand-strong: #173c31;
  --accent: #a64b32;
  --focus: #0b6fc2;
  --shadow: 0 8px 24px rgba(24, 33, 43, 0.08);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans CJK SC",
    "Noto Sans CJK TC", "Hiragino Sans", "Yu Gothic", "Malgun Gothic",
    Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--surface);
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--brand);
  text-underline-offset: 0.18em;
  text-decoration-thickness: 0.08em;
}

a:hover {
  color: var(--accent);
}

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 0.5rem;
  left: 0.5rem;
  padding: 0.65rem 0.9rem;
  color: #ffffff;
  background: var(--brand-strong);
  border-radius: 4px;
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(12px);
}

.header-inner,
.footer-inner,
.page-shell {
  width: min(100% - 2rem, 72rem);
  margin-inline: auto;
}

.header-inner {
  min-height: 4rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand-link {
  display: inline-flex;
  min-width: 0;
  align-items: center;
  gap: 0.65rem;
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
}

.brand-link img {
  width: 2.25rem;
  height: 2.25rem;
  flex: 0 0 auto;
  border-radius: 8px;
}

.language-nav ul,
.footer-links,
.language-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.language-nav ul {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.25rem;
}

.language-nav a {
  display: block;
  min-width: 2.75rem;
  padding: 0.35rem 0.55rem;
  border-radius: 4px;
  color: var(--muted);
  font-size: 0.875rem;
  font-weight: 650;
  text-align: center;
  text-decoration: none;
}

.language-nav a:hover,
.language-nav a[aria-current="page"] {
  color: var(--brand-strong);
  background: var(--surface-soft);
}

main {
  min-height: calc(100vh - 12rem);
}

.hero {
  min-height: min(42rem, calc(100vh - 4rem));
  display: grid;
  align-items: center;
  padding-block: 4.5rem;
  border-bottom: 1px solid var(--line);
  background: var(--surface-soft);
}

.hero-inner {
  width: min(100% - 2rem, 72rem);
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(8rem, 12rem) minmax(0, 1fr);
  align-items: center;
  gap: clamp(2rem, 6vw, 5rem);
}

.app-icon {
  width: 100%;
  height: auto;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.eyebrow {
  margin: 0 0 0.5rem;
  color: var(--accent);
  font-size: 0.875rem;
  font-weight: 750;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.25;
  letter-spacing: 0;
}

h1 {
  max-width: 18ch;
  margin: 0;
  font-size: 3.25rem;
}

h2 {
  margin: 0 0 1rem;
  font-size: 1.75rem;
}

h3 {
  margin: 0 0 0.45rem;
  font-size: 1.05rem;
}

.hero-copy {
  max-width: 42rem;
  margin: 1rem 0 0;
  color: var(--muted);
  font-size: 1.1rem;
}

.language-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-top: 1.75rem;
}

.language-list a {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 0.9rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--ink);
  background: var(--surface);
  font-weight: 700;
  text-decoration: none;
}

.language-list a:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.section {
  padding-block: 4.5rem;
}

.section-intro {
  max-width: 62ch;
  margin: 0 0 2rem;
  color: var(--muted);
}

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

.feature-card {
  min-height: 12rem;
  display: flex;
  flex-direction: column;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-top: 3px solid var(--brand);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 4px 14px rgba(24, 33, 43, 0.04);
}

.feature-card:nth-child(2n) {
  border-top-color: var(--accent);
}

.feature-card p {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.feature-card a {
  margin-top: auto;
  font-weight: 750;
}

.legal-layout {
  width: min(100% - 2rem, 78ch);
  margin-inline: auto;
  padding-block: 3.5rem 5rem;
}

.legal-layout h1 {
  max-width: none;
  font-size: 2.35rem;
}

.legal-layout h2 {
  margin-top: 2.5rem;
  font-size: 1.5rem;
}

.legal-layout h3 {
  margin-top: 1.75rem;
}

.legal-layout p,
.legal-layout li {
  max-width: 78ch;
}

.error-page {
  width: min(100% - 2rem, 48rem);
  margin-inline: auto;
  padding-block: 5rem;
  text-align: center;
}

.error-page .app-icon {
  width: 6rem;
  margin-inline: auto;
  margin-bottom: 1.5rem;
}

.error-code {
  margin: 0 0 0.5rem;
  color: var(--accent);
  font-size: 1rem;
  font-weight: 800;
}

.error-page h1 {
  max-width: none;
  font-size: 2.25rem;
}

.error-page > p:not(.error-code) {
  color: var(--muted);
}

.error-page .language-list {
  justify-content: center;
}

.site-footer {
  padding-block: 2rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  background: var(--surface-soft);
}

.footer-inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
}

.site-footer p {
  margin: 0;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.5rem 1rem;
}

@media (max-width: 760px) {
  .header-inner {
    min-height: auto;
    align-items: flex-start;
    flex-direction: column;
    padding-block: 0.75rem;
  }

  .language-nav ul {
    justify-content: flex-start;
  }

  .hero {
    min-height: auto;
    padding-block: 3rem;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    align-items: start;
    gap: 1.25rem;
  }

  .hero-inner > .app-icon {
    width: 5.5rem;
  }

  h1 {
    font-size: 2rem;
  }

  .language-list li {
    min-width: 0;
    flex: 1 1 8rem;
  }

  .language-list a {
    width: 100%;
  }

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

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

  .footer-links {
    justify-content: flex-start;
  }
}

@media (max-width: 480px) {
  .feature-grid {
    grid-template-columns: 1fr;
  }

  .feature-card {
    min-height: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

@media print {
  :root {
    color: #000000;
    font-size: 11pt;
  }

  .site-header,
  .language-nav,
  .language-list,
  .site-footer,
  .skip-link {
    display: none !important;
  }

  body,
  main,
  .legal-layout {
    width: 100%;
    max-width: none;
    margin: 0;
    padding: 0;
    background: #ffffff;
  }

  a {
    color: #000000;
    text-decoration: underline;
  }

  h1,
  h2,
  h3 {
    break-after: avoid;
  }

  p,
  li {
    orphans: 3;
    widows: 3;
  }
}