:root {
  --bg: #ffffff;
  --bg-alt: #f4f7fb;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #526077;
  --border: #e2e8f0;
  --accent: #2a9df4;
  --accent-strong: #1683d6;
  --accent-soft: #e6f3fe;
  --on-accent: #ffffff;
  --shadow: 0 1px 2px rgba(15, 23, 42, 0.04), 0 8px 24px rgba(15, 23, 42, 0.06);
  --radius: 14px;
  --max: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --bg-alt: #0f1828;
    --surface: #131e31;
    --text: #e6edf7;
    --muted: #9aa8bd;
    --border: #22304a;
    --accent: #3aa8f7;
    --accent-strong: #62bbfa;
    --accent-soft: #10263d;
    --on-accent: #06121f;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.35);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-strong); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  width: 100%;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  color: var(--text);
}
.brand:hover { text-decoration: none; }

.brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: var(--accent);
  color: var(--on-accent);
  display: grid;
  place-items: center;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-links a { color: var(--muted); font-weight: 500; font-size: 15px; }
.nav-links a:hover { color: var(--text); text-decoration: none; }
.nav-links .btn { color: var(--on-accent); }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  padding: 6px 10px;
  font-size: 18px;
  cursor: pointer;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 15px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.15s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-strong); }
.btn-secondary { background: var(--surface); color: var(--text); border-color: var(--border); }
.btn-secondary:hover { border-color: var(--accent); }
.btn-sm { padding: 8px 16px; font-size: 14px; }
.btn svg { width: 18px; height: 18px; flex-shrink: 0; }

/* ---------- Hero ---------- */
.hero {
  padding: 88px 0 72px;
  background:
    radial-gradient(900px 400px at 85% -10%, var(--accent-soft), transparent 70%),
    var(--bg);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 18px;
}

h1 {
  font-size: clamp(34px, 5vw, 52px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 0 0 18px;
}

.lead {
  font-size: 18px;
  color: var(--muted);
  margin: 0 0 28px;
  max-width: 560px;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }

.hero-note {
  margin-top: 18px;
  font-size: 14px;
  color: var(--muted);
}

/* Chat mock */
.chat {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: var(--shadow);
  overflow: hidden;
  max-width: 400px;
  margin-left: auto;
  width: 100%;
}
.chat-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
}
.chat-avatar {
  width: 38px; height: 38px; border-radius: 50%;
  background: var(--accent); color: var(--on-accent);
  display: grid; place-items: center; font-weight: 700;
}
.chat-title { font-weight: 600; font-size: 15px; }
.chat-sub { font-size: 12px; color: var(--muted); }
.chat-body { padding: 18px; display: flex; flex-direction: column; gap: 10px; background: var(--bg-alt); }
.msg {
  max-width: 85%;
  padding: 10px 14px;
  border-radius: 14px;
  font-size: 14px;
  line-height: 1.45;
}
.msg-bot { background: var(--surface); border: 1px solid var(--border); border-bottom-left-radius: 4px; }
.msg-user { align-self: flex-end; background: var(--accent); color: var(--on-accent); border-bottom-right-radius: 4px; }
.msg-buttons { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; margin-top: 8px; }
.msg-buttons span {
  text-align: center;
  padding: 6px;
  border-radius: 8px;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 600;
}

/* ---------- Sections ---------- */
section { padding: 80px 0; }
.section-alt { background: var(--bg-alt); }

.section-head { text-align: center; max-width: 640px; margin: 0 auto 48px; }
.section-head h2 {
  font-size: clamp(26px, 3.5vw, 36px);
  letter-spacing: -0.015em;
  line-height: 1.2;
  margin: 0 0 12px;
}
.section-head p { color: var(--muted); margin: 0; font-size: 17px; }

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  counter-reset: step;
}
.step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.step-num {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--accent-soft); color: var(--accent-strong);
  display: grid; place-items: center; font-weight: 700; margin-bottom: 16px;
}
.step h3 { margin: 0 0 8px; font-size: 18px; }
.step p { margin: 0; color: var(--muted); font-size: 15px; }

/* Features */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.feature {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.feature-icon {
  width: 42px; height: 42px; border-radius: 10px;
  background: var(--accent-soft); color: var(--accent-strong);
  display: grid; place-items: center; margin-bottom: 14px;
}
.feature-icon svg { width: 22px; height: 22px; }
.feature h3 { margin: 0 0 6px; font-size: 17px; }
.feature p { margin: 0; color: var(--muted); font-size: 15px; }

/* Audience */
.audience {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}
.chip {
  padding: 10px 18px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  font-weight: 500;
  font-size: 15px;
}

/* Pricing */
.price-card {
  max-width: 460px;
  margin: 0 auto;
  background: var(--surface);
  border: 2px solid var(--accent);
  border-radius: 20px;
  padding: 36px;
  box-shadow: var(--shadow);
  text-align: center;
}
.price-name { font-weight: 600; color: var(--accent-strong); margin-bottom: 8px; }
.price { font-size: 48px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.1; }
.price small { font-size: 17px; font-weight: 500; color: var(--muted); }
.price-sub { color: var(--muted); margin: 8px 0 24px; font-size: 15px; }
.checklist { list-style: none; padding: 0; margin: 0 0 28px; text-align: left; }
.checklist li {
  display: flex; gap: 10px; align-items: flex-start;
  padding: 8px 0; border-bottom: 1px solid var(--border); font-size: 15px;
}
.checklist li:last-child { border-bottom: none; }
.checklist svg { width: 18px; height: 18px; color: var(--accent); flex-shrink: 0; margin-top: 3px; }
.price-card .btn { width: 100%; }

/* FAQ */
.faq { max-width: 760px; margin: 0 auto; }
.faq details {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0 20px;
  margin-bottom: 12px;
}
.faq summary {
  cursor: pointer;
  list-style: none;
  padding: 18px 0;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--muted); font-size: 20px; line-height: 1; }
.faq details[open] summary::after { content: "−"; }
.faq details p { margin: 0 0 18px; color: var(--muted); }
.code {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  background: var(--accent-soft);
  color: var(--accent-strong);
  padding: 2px 8px;
  border-radius: 6px;
  user-select: all;
}

/* CTA */
.cta {
  text-align: center;
  background: var(--accent);
  color: var(--on-accent);
  border-radius: 24px;
  padding: 56px 24px;
}
.cta h2 { margin: 0 0 10px; font-size: clamp(26px, 3.5vw, 34px); }
.cta p { margin: 0 0 24px; opacity: 0.9; }
.cta .btn { background: var(--on-accent); color: var(--accent-strong); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
  color: var(--muted);
  font-size: 14px;
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 16px;
}
.footer-links { display: flex; flex-wrap: wrap; gap: 20px; }
.footer-links a { color: var(--muted); }

/* ---------- Legal page ---------- */
.legal { padding: 56px 0 80px; }
.legal .container { max-width: 760px; }
.legal h1 { font-size: clamp(30px, 4vw, 40px); }
.legal h2 { font-size: 20px; margin: 36px 0 10px; }
.legal p, .legal li { color: var(--muted); }
.legal ul { padding-left: 22px; }
.legal .meta { color: var(--muted); font-size: 14px; margin-bottom: 32px; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .chat { margin: 0 auto; }
  .features { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 8px 16px 16px;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 0; }
  .nav-links .btn { margin-top: 8px; }
  .hero { padding: 56px 0 48px; }
  section { padding: 56px 0; }
  .features { grid-template-columns: 1fr; }
  .price-card { padding: 28px 20px; }
}

/* ---------- List resets for semantic lists ---------- */
.steps, .audience { list-style: none; margin: 0; padding: 0; }

/* ---------- Breadcrumb / 404 ---------- */
.breadcrumb { font-size: 14px; color: var(--muted); margin-bottom: 16px; }
.breadcrumb a { color: var(--muted); }
.not-found { text-align: center; padding: 120px 0; }
.not-found p { margin: 0 0 24px; }

/* ---------- Custom bot development ---------- */
.custom-card {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 40px;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 40px;
  box-shadow: var(--shadow);
}
.custom-card h2 { font-size: clamp(24px, 3vw, 32px); line-height: 1.2; margin: 0 0 10px; }
.custom-card > div > p { color: var(--muted); margin: 0 0 20px; }
.custom-list { justify-content: flex-start; gap: 10px; }
.custom-list .chip { font-size: 14px; padding: 8px 14px; }
.custom-action { text-align: center; }
.custom-handle { color: var(--muted); font-size: 14px; margin: 12px 0 0; }

@media (max-width: 900px) {
  .custom-card { grid-template-columns: 1fr; padding: 28px 20px; gap: 24px; }
  .custom-action .btn { width: 100%; }
}
@media (min-width: 721px) and (max-width: 960px) {
  .nav-links { gap: 18px; }
}