:root {
  color-scheme: dark;
  --background: #07101d;
  --surface: #0d1a2b;
  --surface-soft: #12233a;
  --border: #263d5a;
  --text: #edf6ff;
  --muted: #a9bdd1;
  --accent: #8ed8ff;
  --accent-strong: #c8edff;
  --content-width: 760px;
}

* {
  box-sizing: border-box;
}

html {
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", "Noto Sans TC", sans-serif;
  background: var(--background);
  color: var(--text);
  font-size: 16px;
  line-height: 1.75;
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 12% 0%, rgba(76, 174, 230, 0.16), transparent 32rem),
    linear-gradient(180deg, #091524 0%, var(--background) 45%);
}

a {
  color: var(--accent);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.2em;
}

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

a:focus-visible {
  border-radius: 0.2rem;
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  top: 0.75rem;
  left: -9999px;
  z-index: 10;
  padding: 0.6rem 0.9rem;
  border-radius: 0.5rem;
  background: var(--text);
  color: var(--background);
}

.skip-link:focus {
  left: 0.75rem;
}

.site-header,
main,
.site-footer {
  width: min(calc(100% - 2rem), var(--content-width));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding-block: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.brand {
  color: var(--text);
  font-size: 1rem;
  font-weight: 720;
  letter-spacing: 0.01em;
  text-decoration: none;
}

nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

nav a {
  color: var(--muted);
  font-size: 0.9rem;
  text-decoration: none;
}

main {
  padding-block: clamp(3rem, 9vw, 6.5rem);
}

.eyebrow {
  margin: 0 0 0.8rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2 {
  line-height: 1.25;
  text-wrap: balance;
}

h1 {
  max-width: 16ch;
  margin: 0;
  font-size: clamp(2.35rem, 8vw, 4.5rem);
  letter-spacing: -0.045em;
}

h2 {
  margin-top: 2.8rem;
  font-size: 1.35rem;
}

.lede {
  max-width: 40rem;
  margin: 1.5rem 0 0;
  color: var(--muted);
  font-size: clamp(1.08rem, 2.5vw, 1.25rem);
}

.summary {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin-top: 3rem;
}

.card {
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: 1rem;
  background: rgba(13, 26, 43, 0.78);
}

.card strong {
  display: block;
  margin-bottom: 0.25rem;
  color: var(--accent-strong);
}

.card p,
.content p,
.content li {
  color: var(--muted);
}

.card p {
  margin: 0;
}

.content {
  max-width: 44rem;
}

.content h1 {
  max-width: none;
  font-size: clamp(2.1rem, 7vw, 3.5rem);
}

.content ul {
  padding-left: 1.25rem;
}

.notice {
  margin-top: 3rem;
  padding: 1rem 1.15rem;
  border-left: 3px solid var(--accent);
  background: var(--surface-soft);
  color: var(--muted);
}

.meta {
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 1.5rem 2.5rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.88rem;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 620px) {
  .site-header,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

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