:root {
  color-scheme: light;
  --bg: #fbfbfe;
  --surface: #ffffff;
  --panel: #f1f2fa;
  --text: #1c1d27;
  --muted: #686c80;
  --line: #e6e7f2;
  --accent: #6d5bf0;
  --accent-strong: #5847d8;
  --accent-weak: #ecebfd;
  --brand-1: #4f6df5;
  --brand-2: #8b5cf6;
  --brand-3: #14b8a6;
  --shadow-sm: 0 1px 3px rgba(20, 20, 50, 0.07);
  --shadow-md: 0 16px 40px -16px rgba(30, 35, 90, 0.22);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Segoe UI",
    "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  line-height: 1.5;
  position: relative;
  overflow-x: hidden;
}

.bg-decor {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: radial-gradient(680px 480px at 8% -10%, rgba(79, 109, 245, 0.12), transparent 60%),
    radial-gradient(620px 460px at 108% 6%, rgba(20, 184, 166, 0.1), transparent 60%),
    radial-gradient(700px 520px at 50% 110%, rgba(139, 92, 246, 0.08), transparent 60%);
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1,
h2,
h3,
p {
  margin: 0;
}

.grad {
  background: linear-gradient(100deg, var(--brand-1), var(--brand-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.eyebrow {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--accent-strong);
  text-transform: uppercase;
  margin-bottom: 10px;
}

/* buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: 10px;
  font-weight: 650;
  font-size: 14px;
  white-space: nowrap;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.btn-primary {
  background: linear-gradient(100deg, var(--brand-1), var(--accent));
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.btn-ghost {
  background: var(--panel);
  color: var(--text);
}

.btn-ghost:hover {
  background: var(--accent-weak);
}

.btn.lg {
  padding: 13px 24px;
  font-size: 15px;
}

/* nav */

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(251, 251, 254, 0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  width: min(1160px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 24px;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 750;
  font-size: 16px;
  margin-right: auto;
}

.brand-mark {
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--brand-1), var(--brand-2), var(--brand-3));
  flex-shrink: 0;
}

.brand-text small {
  display: block;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  cursor: pointer;
  margin-left: -8px;
}

.nav-toggle span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--text);
}

/* hero */

main {
  width: min(1160px, calc(100% - 32px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 48px;
  align-items: center;
  padding: 72px 0 56px;
}

.hero h1 {
  font-size: 44px;
  line-height: 1.18;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.lede {
  margin-top: 18px;
  font-size: 16px;
  color: var(--muted);
  max-width: 540px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  margin-top: 28px;
  flex-wrap: wrap;
}

.hero-actions.center {
  justify-content: center;
}

.hero-stats {
  display: flex;
  gap: 32px;
  margin-top: 40px;
}

.hero-stats div {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero-stats strong {
  font-size: 22px;
  font-weight: 800;
}

.hero-stats span {
  font-size: 13px;
  color: var(--muted);
}

/* demo card */

.hero-visual {
  display: flex;
  justify-content: center;
}

.demo-card {
  width: 100%;
  max-width: 420px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.demo-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--line);
}

.dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
}

.dot-red {
  background: #ff5f57;
}

.dot-amber {
  background: #febc2e;
}

.dot-green {
  background: #28c840;
}

.demo-title {
  margin-left: 8px;
  font-size: 12px;
  font-weight: 650;
  color: var(--muted);
}

.demo-chat {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.bubble {
  position: relative;
  padding: 10px 12px;
  border-radius: 12px;
  font-size: 13px;
  line-height: 1.5;
  max-width: 92%;
  background: var(--panel);
}

.bubble .who {
  display: block;
  font-size: 11px;
  font-weight: 700;
  color: var(--muted);
  margin-bottom: 3px;
}

.bubble-user {
  align-self: flex-end;
  background: var(--accent-weak);
}

.bubble-bot {
  align-self: flex-start;
}

.bubble-bot.ok {
  background: rgba(20, 184, 166, 0.12);
}

.demo-arrow {
  text-align: center;
  font-size: 12px;
  font-weight: 650;
  color: var(--muted);
  padding-bottom: 8px;
}

.demo-json {
  margin: 0 16px 16px;
  padding: 14px;
  border-radius: 10px;
  background: #15161e;
  color: #c7e8ff;
  font-size: 12px;
  line-height: 1.6;
  overflow-x: auto;
}

/* logos strip */

.logos {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
  padding: 24px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.logos > span:first-child {
  font-size: 13px;
  color: var(--muted);
  font-weight: 600;
}

.logo-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.chip {
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--panel);
  font-size: 13px;
  font-weight: 650;
  color: var(--text);
}

/* sections */

.section {
  padding: 72px 0;
}

.section-head {
  max-width: 640px;
  margin: 0 auto 40px;
  text-align: center;
}

.section-head h2 {
  font-size: 30px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.section-lede {
  margin-top: 12px;
  color: var(--muted);
  font-size: 15px;
}

.grid {
  display: grid;
  gap: 18px;
}

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

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

.card,
.pillar {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px;
}

.card h3,
.pillar h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

.card p,
.pillar p {
  font-size: 14px;
  color: var(--muted);
}

.pillar {
  background: linear-gradient(180deg, var(--surface), var(--panel));
}

.pillar-no {
  display: block;
  font-size: 13px;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 10px;
}

/* architecture pipeline */

.pipeline {
  display: flex;
  align-items: stretch;
  gap: 14px;
}

.layer {
  flex: 1;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px;
}

.layer-head {
  margin-bottom: 14px;
}

.layer-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--accent-strong);
  background: var(--accent-weak);
  border-radius: 999px;
  padding: 3px 10px;
  margin-bottom: 10px;
}

.layer h3 {
  font-size: 18px;
  font-weight: 750;
}

.layer-sub {
  font-size: 13px;
  color: var(--muted);
  margin-top: 2px;
}

.layer ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.layer li {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
  padding-left: 16px;
  position: relative;
}

.layer li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand-2);
}

.layer code {
  background: var(--panel);
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 12px;
}

.layer-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  color: var(--muted);
  flex-shrink: 0;
}

/* integration */

.integration-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
}

.integration-side {
  flex: 1;
  max-width: 280px;
}

.integration-side h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
  margin-bottom: 12px;
}

.integration-side:last-child {
  text-align: right;
}

.integration-side:last-child .chip-group {
  justify-content: flex-end;
}

.chip-group {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.integration-core {
  flex-shrink: 0;
  width: 180px;
  height: 90px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font-size: 14px;
  font-weight: 750;
  color: #fff;
  background: linear-gradient(120deg, var(--brand-1), var(--accent), var(--brand-2));
  box-shadow: var(--shadow-md);
  padding: 10px;
}

/* cta band */

.cta-band {
  margin: 24px 0 72px;
  padding: 56px 32px;
  border-radius: 24px;
  text-align: center;
  background: linear-gradient(135deg, #11132a, #1d1f3d);
  color: #fff;
}

.cta-band h2 {
  font-size: 28px;
  font-weight: 800;
  line-height: 1.3;
}

.cta-band .grad {
  background: linear-gradient(100deg, #8bb4ff, #c8a8ff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.cta-band p {
  margin-top: 14px;
  color: rgba(255, 255, 255, 0.7);
}

.cta-band .btn-ghost {
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
}

/* footer */

.site-footer {
  border-top: 1px solid var(--line);
  padding: 32px 0 40px;
}

.footer-top {
  width: min(1160px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-links {
  display: flex;
  gap: 22px;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
}

.footer-links a:hover {
  color: var(--text);
}

.footer-meta {
  width: min(1160px, calc(100% - 32px));
  margin: 18px auto 0;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 12px;
  color: var(--muted);
}

/* responsive */

@media (max-width: 920px) {
  .hero {
    grid-template-columns: 1fr;
    padding: 48px 0 40px;
    text-align: center;
  }

  .hero h1 {
    font-size: 34px;
  }

  .lede {
    margin-inline: auto;
  }

  .hero-actions,
  .hero-stats {
    justify-content: center;
  }

  .hero-visual {
    margin-top: 8px;
  }

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

  .grid-3 {
    grid-template-columns: 1fr;
  }

  .pipeline {
    flex-direction: column;
  }

  .layer-arrow {
    transform: rotate(90deg);
  }

  .integration-row {
    flex-direction: column;
  }

  .integration-side:last-child {
    text-align: center;
  }

  .integration-side:last-child .chip-group {
    justify-content: center;
  }
}

@media (max-width: 720px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-md);
    padding: 8px 16px;
    display: none;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    width: 100%;
    padding: 12px 0;
    border-bottom: 1px solid var(--line);
  }

  .nav-links a:last-child {
    border-bottom: none;
  }

  .nav-cta .btn {
    padding: 9px 14px;
    font-size: 13px;
  }
}

@media (max-width: 560px) {
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 56px 0;
  }

  .cta-band {
    padding: 40px 20px;
  }
}