:root {
  --bg: #f3f5f8;
  --bg-soft: #eaf1f9;
  --bg-panel: rgba(255, 255, 255, 0.74);
  --surface: #ffffff;
  --surface-strong: #f8fafc;
  --line: rgba(12, 26, 40, 0.12);
  --text: #0f1720;
  --muted: #5a6877;
  --primary: #0078d4;
  --primary-dark: #0d5fb7;
  --primary-soft: rgba(0, 120, 212, 0.12);
  --accent: #2f7d66;
  --shadow: rgba(9, 18, 32, 0.08);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--bg);
}

body {
  margin: 0;
  font-family: "Segoe UI", Inter, Helvetica, Arial, sans-serif;
  background: linear-gradient(180deg, #f3f5f8 0%, #f6f8fb 100%);
  color: var(--text);
  line-height: 1.6;
}

img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
}

.container {
  width: min(1160px, calc(100% - 2rem));
  margin: 0 auto;
}

.narrow {
  width: min(1040px, calc(100% - 2rem));
}

.hero {
  background:
    radial-gradient(circle at top left, rgba(0, 120, 212, 0.12), transparent 30%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(243, 245, 248, 0.98));
  border-bottom: 1px solid var(--line);
  padding: 1.2rem 0 4rem;
}

.nav {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr) auto;
  align-items: center;
  gap: 1rem;
  padding: 0.2rem 0 1rem;
}

.brand {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text);
}

.nav-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1.15rem;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  transition: color 0.2s ease;
}

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

.lang-toggle {
  display: inline-flex;
  align-items: center;
  justify-self: end;
  gap: 0.35rem;
  padding: 0.3rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 8px 18px rgba(15, 23, 32, 0.03);
}

.lang-button {
  border: 0;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 0.48rem 0.82rem;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.lang-button.active {
  color: #fff;
  background: linear-gradient(180deg, #0a92ff 0%, #0078d4 100%);
  box-shadow: 0 10px 18px rgba(0, 120, 212, 0.25);
}

.hero-content {
  padding-top: 3.5rem;
}

.eyebrow {
  margin: 0 0 1rem;
  color: var(--accent);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin: 0 0 0.9rem;
  line-height: 1.06;
  letter-spacing: -0.05em;
}

h1 {
  max-width: 760px;
  font-size: clamp(2.7rem, 5vw, 5rem);
}

h2 {
  max-width: 900px;
  font-size: clamp(2rem, 3vw, 3.2rem);
}

h3 {
  font-size: 1.28rem;
  letter-spacing: -0.04em;
}

.lead {
  max-width: 750px;
  margin: 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.9rem 1.5rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
}

.button.primary {
  background: linear-gradient(180deg, #0a90ff 0%, #0078d4 100%);
  color: #fff;
  box-shadow: 0 16px 30px rgba(0, 120, 212, 0.2);
}

.button.secondary {
  color: var(--text);
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--line);
}

.section {
  padding: 5rem 0;
}

.section.alt {
  background: rgba(255, 255, 255, 0.4);
  border-top: 1px solid rgba(15, 23, 32, 0.04);
  border-bottom: 1px solid rgba(15, 23, 32, 0.04);
}

.section-heading {
  margin-bottom: 2rem;
}

.grid.two-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.2rem;
}

.card {
  padding: 1.6rem 1.5rem;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: 0 12px 28px rgba(17, 24, 39, 0.04);
}

.card p,
.feature-list p,
.arch-caption {
  margin: 0;
  color: var(--muted);
}

.feature-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.2rem;
}

.feature-list > div {
  padding: 1.4rem;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 12px 24px rgba(15, 23, 32, 0.02);
}

.feature-list strong {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
  color: var(--text);
}

.demo-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.9fr);
  gap: 1.4rem;
  align-items: center;
}

.demo-preview {
  position: relative;
  min-height: 360px;
  border-radius: 28px;
  border: 1px solid var(--line);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(0, 120, 212, 0.18), rgba(47, 125, 102, 0.12)),
    linear-gradient(180deg, #0d1723 0%, #142338 100%);
  box-shadow: 0 18px 40px rgba(15, 23, 32, 0.12);
}

.demo-preview::before {
  content: "";
  position: absolute;
  inset: 16% 12% auto auto;
  width: 54%;
  height: 54%;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.04);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.05);
}

.demo-preview::after {
  content: "";
  position: absolute;
  inset: 22% 18% 10% 18%;
  background: linear-gradient(180deg, rgba(0, 120, 212, 0.38), rgba(45, 93, 160, 0.18));
  border-radius: 22px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  transform: skewY(-4deg);
}

.demo-overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  z-index: 1;
}

.demo-play {
  display: inline-grid;
  place-items: center;
  width: 90px;
  height: 90px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.16);
  border: 1px solid rgba(255, 255, 255, 0.24);
  color: #fff;
  font-size: 2rem;
  backdrop-filter: blur(6px);
  box-shadow: 0 18px 30px rgba(0, 0, 0, 0.2);
}

.demo-metadata {
  position: absolute;
  left: 1.4rem;
  right: 1.4rem;
  bottom: 1.2rem;
  z-index: 1;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: end;
  color: #edf6ff;
}

.demo-metadata span {
  opacity: 0.8;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.demo-metadata strong {
  font-size: 1rem;
  line-height: 1.2;
}

.demo-copy {
  display: grid;
  gap: 1.25rem;
}

.demo-copy p {
  margin: 0;
  color: var(--muted);
  font-size: 1.04rem;
}

.architecture-wrap {
  display: grid;
  gap: 1.4rem;
}

.architecture-visual,
.flow-panel {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(244, 248, 252, 0.96));
  border: 1px solid rgba(12, 26, 40, 0.08);
  border-radius: 26px;
  box-shadow: 0 18px 38px rgba(15, 23, 32, 0.05);
}

.architecture-visual {
  padding: 0.8rem;
}

.flow-panel {
  padding: 1rem 1rem 0.6rem;
}

.flow-header {
  margin: 0 0 0.7rem;
  text-align: center;
  color: var(--text);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 700;
}

.architecture-svg,
.flow-svg {
  border-radius: 18px;
}

.arch-caption {
  max-width: 760px;
  margin: 0 auto;
  text-align: center;
}

.footer {
  padding: 1.5rem 0 3rem;
  color: var(--muted);
  text-align: center;
  border-top: 1px solid var(--line);
}

@media (max-width: 760px) {
  .nav {
    grid-template-columns: 1fr;
    justify-items: flex-start;
  }

  .nav-links {
    justify-content: flex-start;
  }

  .lang-toggle {
    justify-self: flex-start;
  }

  .grid.two-columns,
  .feature-list,
  .demo-panel {
    grid-template-columns: 1fr;
  }

  .demo-preview {
    min-height: 280px;
  }

  .section {
    padding: 4rem 0;
  }
}