:root {
  --primary: #4f6ef7;
  --primary-dark: #3b55e0;
  --accent: #8b5cf6;
  --bg: #ffffff;
  --bg-alt: #f5f7ff;
  --text: #1f2430;
  --text-muted: #5b6472;
  --radius: 14px;
  --shadow: 0 10px 40px rgba(79, 110, 247, 0.12);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}

img {
  max-width: 100%;
}

.container {
  width: min(1140px, 92%);
  margin-inline: auto;
}

.grid {
  display: grid;
  gap: 24px;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.btn {
  display: inline-block;
  padding: 13px 32px;
  border-radius: 999px;
  font-size: 1rem;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  box-shadow: 0 8px 20px rgba(79, 110, 247, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(79, 110, 247, 0.45);
}

.btn-ghost {
  color: var(--primary);
  background: transparent;
  border: 1.5px solid rgba(79, 110, 247, 0.45);
}

.btn-ghost:hover {
  background: rgba(79, 110, 247, 0.08);
}

.btn-sm { padding: 9px 22px; font-size: 0.9rem; }
.btn-block { width: 100%; }

.navbar {
  position: fixed;
  inset-inline: 0;
  top: 0;
  z-index: 100;
  padding: 16px 0;
  transition: background 0.3s ease, box-shadow 0.3s ease, padding 0.3s ease;
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 18px rgba(31, 36, 48, 0.08);
  padding: 10px 0;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
}

.logo-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-weight: 700;
  font-size: 1.25rem;
}

.logo-text {
  font-weight: 700;
  font-size: 1.15rem;
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.logo-text small {
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 2px;
  color: var(--text-muted);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 26px;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--primary);
}

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: 90px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 15% 25%, rgba(139, 92, 246, 0.14), transparent 45%),
    radial-gradient(circle at 85% 20%, rgba(79, 110, 247, 0.16), transparent 50%),
    radial-gradient(circle at 60% 90%, rgba(79, 110, 247, 0.1), transparent 45%);
}

.hero-inner {
  position: relative;
  text-align: center;
}

.hero-tagline {
  display: inline-block;
  padding: 6px 18px;
  border-radius: 999px;
  background: rgba(79, 110, 247, 0.1);
  color: var(--primary);
  font-size: 0.88rem;
  letter-spacing: 3px;
  margin-bottom: 22px;
}

.hero h1 {
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 800;
  letter-spacing: 1px;
}

.gradient-text {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 640px;
  margin: 20px auto 34px;
  color: var(--text-muted);
  font-size: 1.06rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-mockup {
  margin: 56px auto 0;
  max-width: 560px;
  perspective: 900px;
}

.chat-card {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(79, 110, 247, 0.15);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.chat-head {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 12px 16px;
  border-bottom: 1px solid rgba(31, 36, 48, 0.06);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.chat-head i {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #ff5f57;
}

.chat-head i:nth-child(2) { background: #febc2e; }
.chat-head i:nth-child(3) { background: #28c840; }
.chat-head i + .chat-head i ~ * { margin-left: auto; }

.chat-body {
  padding: 18px 16px 22px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: left;
}

.msg {
  max-width: 80%;
  padding: 10px 16px;
  border-radius: 14px;
  font-size: 0.92rem;
}

.msg.user {
  align-self: flex-end;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  border-bottom-right-radius: 4px;
}

.msg.bot {
  align-self: flex-start;
  background: var(--bg-alt);
  border-bottom-left-radius: 4px;
}

.section {
  padding: 96px 0;
}

.alt-bg {
  background: var(--bg-alt);
}

.section-title {
  text-align: center;
  font-size: clamp(1.7rem, 3.5vw, 2.3rem);
  font-weight: 800;
  margin-bottom: 10px;
}

.section-sub {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 52px;
}

.card {
  background: #fff;
  border-radius: var(--radius);
  padding: 34px 28px;
  box-shadow: 0 4px 24px rgba(31, 36, 48, 0.06);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.card .icon {
  font-size: 2rem;
  width: 62px;
  height: 62px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(79, 110, 247, 0.12), rgba(139, 92, 246, 0.14));
  margin-bottom: 18px;
}

.card h3 {
  font-size: 1.15rem;
  margin-bottom: 8px;
}

.card p {
  color: var(--text-muted);
  font-size: 0.94rem;
}

.product-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 34px 28px;
  box-shadow: 0 4px 24px rgba(31, 36, 48, 0.06);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.product-card.main {
  grid-column: span 2;
  background: linear-gradient(135deg, #f0f4ff 0%, #f8f6ff 100%);
  border: 1.5px solid rgba(79, 110, 247, 0.15);
  padding: 44px 38px;
}

.product-badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 999px;
  font-size: 0.78rem;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  margin-bottom: 18px;
  align-self: flex-start;
}

.product-icon {
  font-size: 2.2rem;
  margin-bottom: 14px;
}

.product-card h3 {
  font-size: 1.25rem;
  margin-bottom: 10px;
}

.product-card p {
  color: var(--text-muted);
  font-size: 0.94rem;
  margin-bottom: 18px;
}

.product-features {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 22px;
}

.product-features li::before {
  content: "✓";
  display: inline-block;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(79, 110, 247, 0.1);
  color: var(--primary);
  font-size: 0.75rem;
  text-align: center;
  line-height: 22px;
  margin-right: 8px;
}

.solution-card {
  position: relative;
  background: #fff;
  border-radius: var(--radius);
  padding: 38px 30px 32px;
  box-shadow: 0 4px 24px rgba(31, 36, 48, 0.05);
  overflow: hidden;
  transition: transform 0.25s ease;
}

.solution-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  opacity: 0;
  transition: opacity 0.25s ease;
}

.solution-card:hover {
  transform: translateY(-5px);
}

.solution-card:hover::before {
  opacity: 1;
}

.badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 999px;
  font-size: 0.78rem;
  background: rgba(79, 110, 247, 0.1);
  color: var(--primary);
  margin-bottom: 14px;
}

.solution-card h3 {
  font-size: 1.2rem;
  margin-bottom: 10px;
}

.solution-card p {
  color: var(--text-muted);
  font-size: 0.94rem;
}

.stats {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
}

.stats .section-title { color: #fff; }

.stat-grid { text-align: center; }

.stat strong {
  display: block;
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800;
}

.stat span {
  font-size: 0.95rem;
  opacity: 0.9;
}

.quote-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 30px 28px;
  box-shadow: 0 4px 24px rgba(31, 36, 48, 0.05);
}

.quote-card blockquote {
  font-size: 0.98rem;
  color: var(--text);
  margin-bottom: 18px;
}

.quote-card blockquote::before {
  content: "\201C";
  display: block;
  font-size: 2.6rem;
  line-height: 1;
  color: var(--primary);
  opacity: 0.35;
}

.quote-card figcaption {
  font-size: 0.86rem;
  color: var(--text-muted);
}

.footer {
  background: #14171f;
  color: rgba(255, 255, 255, 0.75);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-name { font-weight: 700; color: #fff; }
.footer-copy { font-size: 0.82rem; opacity: 0.65; }

.footer-links {
  display: flex;
  gap: 22px;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.75);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s ease;
}

.footer-links a:hover { color: #fff; }

.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.menu-toggle span {
  width: 24px;
  height: 2.5px;
  border-radius: 2px;
  background: var(--text);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.menu-toggle.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }

  .menu-toggle { display: flex; }

  .nav-links {
    position: fixed;
    top: 64px;
    inset-inline: 0;
    flex-direction: column;
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(10px);
    padding: 26px 0;
    gap: 20px;
    box-shadow: 0 12px 24px rgba(31, 36, 48, 0.08);
    transform: translateY(-130%);
    transition: transform 0.3s ease;
  }

  .nav-links.open { transform: translateY(0); }
}

@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .section { padding: 72px 0; }
}