:root {
  color-scheme: dark;
  --bg: #030713;
  --surface: rgba(14, 26, 61, 0.72);
  --surface-strong: #101d43;
  --line: rgba(139, 183, 255, 0.18);
  --text: #f4f8ff;
  --muted: #a9b7d4;
  --cyan: #4ce8ff;
  --blue: #5e82ff;
  --purple: #a672ff;
  --green: #72f1b8;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.34);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 18% -8%, rgba(32, 91, 255, 0.34), transparent 38rem),
    radial-gradient(circle at 88% 12%, rgba(136, 73, 255, 0.22), transparent 30rem),
    var(--bg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Noto Sans TC", sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.site-shell {
  width: min(100% - 32px, 980px);
  margin: 0 auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 22px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--text);
  font-weight: 750;
  text-decoration: none;
  letter-spacing: .01em;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: 0 0 28px rgba(76, 232, 255, .2);
}

.site-nav {
  display: flex;
  gap: 6px;
}

.site-nav a {
  padding: 8px 12px;
  border-radius: 10px;
  color: var(--muted);
  font-size: .92rem;
  font-weight: 650;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.site-nav a[aria-current="page"] {
  color: var(--text);
  background: rgba(255, 255, 255, .08);
  outline: none;
}

.hero {
  display: grid;
  grid-template-columns: 1fr 230px;
  align-items: center;
  gap: 56px;
  padding: 88px 0 70px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  color: var(--cyan);
  font-size: .84rem;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 16px var(--green);
}

h1, h2, h3 { line-height: 1.22; }

h1 {
  max-width: 720px;
  margin: 0;
  font-size: clamp(2.5rem, 7vw, 4.15rem);
  letter-spacing: -.055em;
}

.gradient-text {
  color: transparent;
  background: linear-gradient(105deg, #fff 12%, var(--cyan) 52%, #b895ff 90%);
  background-clip: text;
  -webkit-background-clip: text;
}

.lede {
  max-width: 660px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: clamp(1.05rem, 2.4vw, 1.22rem);
}

.hero-icon {
  width: 100%;
  height: auto;
  border-radius: 26%;
  box-shadow: 0 30px 90px rgba(28, 79, 255, .34), 0 0 48px rgba(76, 232, 255, .13);
  transform: rotate(2deg);
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 72px;
}

.quick-card {
  position: relative;
  display: block;
  min-height: 190px;
  padding: 28px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: linear-gradient(145deg, rgba(18, 37, 84, .84), rgba(9, 18, 44, .74));
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease;
}

.quick-card::after {
  content: "↗";
  position: absolute;
  right: 24px;
  bottom: 20px;
  color: var(--cyan);
  font-size: 1.45rem;
}

.quick-card:hover,
.quick-card:focus-visible {
  transform: translateY(-3px);
  border-color: rgba(76, 232, 255, .52);
  outline: none;
}

.card-kicker {
  color: var(--cyan);
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .1em;
}

.quick-card h2 {
  margin: 10px 0 8px;
  font-size: 1.5rem;
}

.quick-card p { margin: 0; color: var(--muted); }

.page-heading {
  padding: 70px 0 40px;
  border-bottom: 1px solid var(--line);
}

.page-heading h1 { font-size: clamp(2.4rem, 6vw, 4.2rem); }
.page-heading .lede { max-width: 720px; }

.content-layout {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: 54px;
  padding: 52px 0 84px;
}

.toc {
  position: sticky;
  top: 22px;
  align-self: start;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(10, 20, 48, .64);
}

.toc strong { display: block; margin-bottom: 8px; }
.toc a { display: block; padding: 6px 0; color: var(--muted); text-decoration: none; }
.toc a:hover { color: var(--cyan); }

.article section {
  padding: 0 0 34px;
  scroll-margin-top: 24px;
}

.article h2 {
  margin: 0 0 12px;
  font-size: 1.55rem;
}

.article p, .article li { color: #c5d0e6; }
.article ul, .article ol { padding-left: 1.25rem; }
.article li + li { margin-top: 8px; }

.info-box {
  margin: 18px 0;
  padding: 20px 22px;
  border: 1px solid rgba(76, 232, 255, .25);
  border-radius: 18px;
  background: rgba(24, 73, 123, .22);
}

.contact-card {
  padding: 26px;
  border: 1px solid rgba(76, 232, 255, .3);
  border-radius: 22px;
  background: linear-gradient(140deg, rgba(22, 62, 125, .55), rgba(29, 21, 71, .55));
}

.contact-card a {
  display: inline-block;
  margin-top: 8px;
  color: var(--cyan);
  font-size: 1.05rem;
  font-weight: 750;
  word-break: break-word;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 26px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: .9rem;
}

.site-footer nav { display: flex; gap: 16px; }
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--text); }

@media (max-width: 720px) {
  .site-header { align-items: flex-start; }
  .site-nav { flex-wrap: wrap; justify-content: flex-end; }
  .site-nav a { padding: 6px 8px; font-size: .84rem; }
  .hero { grid-template-columns: 1fr; gap: 36px; padding: 56px 0 52px; }
  .hero-icon { width: 150px; }
  .quick-grid { grid-template-columns: 1fr; }
  .content-layout { grid-template-columns: 1fr; gap: 28px; }
  .toc { position: static; }
  .site-footer { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .quick-card { transition: none; }
}