:root {
  --ink: #0c1a1f;
  --ink-soft: #1a333c;
  --paper: #f3f0e8;
  --paper-dim: #e5e0d4;
  --accent: #0d9488;
  --accent-deep: #0f766e;
  --accent-glow: rgba(13, 148, 136, 0.35);
  --gold: #c4a35a;
  --muted: #5c6f76;
  --line: rgba(12, 26, 31, 0.1);
  --ok: #0d9488;
  --radius: 18px;
  --font-display: "Syne", "Noto Sans SC", sans-serif;
  --font-body: "Noto Sans SC", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
}

.bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(13, 148, 136, 0.18), transparent 55%),
    radial-gradient(ellipse 60% 40% at 90% 10%, rgba(196, 163, 90, 0.16), transparent 50%),
    radial-gradient(ellipse 50% 60% at 50% 100%, rgba(15, 118, 110, 0.12), transparent 55%),
    linear-gradient(165deg, #f7f4ec 0%, #ebe6da 45%, #e0ebe8 100%);
}

.bg::after {
  content: "";
  position: absolute;
  inset: 0;
  opacity: 0.35;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.45'/%3E%3C/svg%3E");
  pointer-events: none;
  mix-blend-mode: multiply;
}

nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1120px;
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
  animation: fadeDown 0.7s ease both;
}

.logo {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.03em;
  color: var(--ink);
  text-decoration: none;
}

.logo span { color: var(--accent); }

.nav-links {
  display: flex;
  gap: 1.75rem;
  list-style: none;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a.active { color: var(--ink); }

.nav-cta {
  display: inline-flex;
  align-items: center;
  padding: 0.55rem 1.1rem;
  background: var(--ink);
  color: var(--paper);
  border-radius: 999px;
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 600;
  transition: transform 0.2s, background 0.2s;
}

.nav-cta:hover {
  background: var(--accent-deep);
  transform: translateY(-1px);
}

.hero {
  max-width: 1120px;
  margin: 0 auto;
  padding: 3.5rem 1.5rem 2.5rem;
  text-align: center;
  animation: fadeUp 0.8s 0.1s ease both;
}

.hero.hero-compact {
  padding: 2.5rem 1.5rem 1.5rem;
}

.brand-mark {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 8vw, 5.5rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 0.95;
  color: var(--ink);
  margin-bottom: 1.25rem;
}

.brand-mark em {
  font-style: normal;
  background: linear-gradient(120deg, var(--accent) 0%, var(--accent-deep) 50%, var(--gold) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.brand-mark.brand-sm {
  font-size: clamp(2rem, 5vw, 3rem);
  margin-bottom: 0.85rem;
}

.hero h1 {
  font-size: clamp(1.15rem, 2.5vw, 1.45rem);
  font-weight: 500;
  color: var(--ink-soft);
  margin-bottom: 0.65rem;
}

.hero p {
  max-width: 440px;
  margin: 0 auto 1.75rem;
  color: var(--muted);
  font-size: 0.98rem;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.5rem;
  border-radius: 999px;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 8px 28px var(--accent-glow);
}

.btn-primary:hover {
  background: var(--accent-deep);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--line);
}

.btn-ghost:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.section {
  max-width: 1120px;
  margin: 0 auto;
  padding: 1rem 1.5rem 3.5rem;
  animation: fadeUp 0.9s 0.25s ease both;
}

.section-label {
  text-align: center;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-deep);
  margin-bottom: 0.5rem;
}

.section-title {
  text-align: center;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 2rem;
}

.section-lead {
  text-align: center;
  color: var(--muted);
  max-width: 480px;
  margin: -1.25rem auto 2rem;
  font-size: 0.95rem;
}

.glass {
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(12, 26, 31, 0.08);
  backdrop-filter: blur(12px);
  border-radius: calc(var(--radius) + 6px);
}

.footer-cta {
  max-width: 720px;
  margin: 0 auto 4rem;
  padding: 2.5rem 2rem;
  text-align: center;
  border-radius: calc(var(--radius) + 8px);
  background:
    linear-gradient(135deg, rgba(13, 148, 136, 0.12), rgba(196, 163, 90, 0.1)),
    rgba(255, 255, 255, 0.4);
  border: 1px solid rgba(13, 148, 136, 0.2);
  animation: fadeUp 1s 0.45s ease both;
}

.footer-cta h2 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.footer-cta p {
  color: var(--muted);
  margin-bottom: 1.25rem;
  font-size: 0.95rem;
}

.site-footer {
  text-align: center;
  padding: 1.5rem;
  color: var(--muted);
  font-size: 0.8rem;
  border-top: 1px solid var(--line);
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(22px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeDown {
  from { opacity: 0; transform: translateY(-14px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 820px) {
  nav {
    flex-wrap: wrap;
    gap: 0.75rem;
  }
  .nav-links {
    order: 3;
    width: 100%;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
  }
  .nav-cta { margin-left: auto; }
}

/* —— Home —— */
.service-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.service-link {
  display: block;
  text-decoration: none;
  color: inherit;
  border-radius: var(--radius);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.4);
  border: 1px solid rgba(12, 26, 31, 0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s;
}

.service-link:hover {
  transform: translateY(-4px);
  border-color: rgba(13, 148, 136, 0.35);
  box-shadow: 0 12px 32px rgba(12, 26, 31, 0.1);
}

.service-link img {
  display: block;
  width: 100%;
  height: auto;
}

.demo-video {
  display: block;
  width: 100%;
  max-width: 900px;
  margin: 0 auto 2.5rem;
  border-radius: calc(var(--radius) + 4px);
  background: var(--ink);
  border: 1px solid rgba(12, 26, 31, 0.1);
  overflow: hidden;
}

.articles-panel {
  max-width: 820px;
  margin: 0 auto;
  padding: 0;
  overflow: hidden;
}

.articles-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 1.1rem 1.35rem;
  border: none;
  background: transparent;
  color: var(--ink);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  text-align: left;
}

.articles-toggle:hover { color: var(--accent-deep); }

.articles-hint {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--muted);
  white-space: nowrap;
}

.articles-list {
  border-top: 1px solid var(--line);
  padding: 0.5rem 0.75rem 1rem;
  max-height: 420px;
  overflow-y: auto;
}

.articles-list[hidden] { display: none !important; }

.articles-list a {
  display: block;
  padding: 0.7rem 0.6rem;
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.9rem;
  border-bottom: 1px solid rgba(12, 26, 31, 0.06);
  transition: color 0.2s, padding-left 0.2s;
}

.articles-list a:last-child { border-bottom: none; }

.articles-list a:hover {
  color: var(--accent-deep);
  padding-left: 0.85rem;
}

@media (max-width: 900px) {
  .service-grid { grid-template-columns: repeat(2, 1fr); }
}

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

/* —— Updates —— */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.85rem;
}

.article-link {
  display: flex;
  align-items: center;
  padding: 1rem 1.15rem;
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.9rem;
  font-weight: 500;
  line-height: 1.45;
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid rgba(12, 26, 31, 0.08);
  border-radius: 14px;
  backdrop-filter: blur(8px);
  transition: transform 0.25s, border-color 0.25s, background 0.25s;
}

.article-link:hover {
  transform: translateY(-2px);
  border-color: rgba(13, 148, 136, 0.4);
  background: rgba(13, 148, 136, 0.06);
  color: var(--ink);
}

@media (max-width: 720px) {
  .article-grid { grid-template-columns: 1fr; }
}

/* —— WeChat —— */
.wx-layout {
  max-width: 560px;
  margin: 0 auto;
  text-align: center;
}

.wx-intro {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 1.75rem;
  text-align: left;
}

.wx-intro b { color: var(--ink); font-weight: 700; }

.wx-panel {
  padding: 2rem 1.75rem 1.75rem;
}

.wx-panel h2 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
}

.wx-panel .sub {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}

.wx-qr {
  display: block;
  width: min(100%, 320px);
  height: auto;
  margin: 0 auto;
  border-radius: 14px;
  background: rgba(12, 26, 31, 0.04);
}

.wx-tips {
  list-style: none;
  margin: 1.5rem auto 0;
  max-width: 400px;
  text-align: left;
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.75;
}

.wx-tips li {
  position: relative;
  padding-left: 1.1rem;
  margin: 0.45rem 0;
}

.wx-tips li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.4rem;
  height: 0.4rem;
  border-radius: 50%;
  background: var(--accent);
}

.wx-note {
  margin: 1.5rem 0 0;
  padding: 1rem 1.15rem;
  border-radius: 12px;
  background: rgba(13, 148, 136, 0.1);
  border: 1px solid rgba(13, 148, 136, 0.22);
  color: var(--accent-deep);
  font-size: 0.88rem;
  line-height: 1.7;
  text-align: left;
}