:root {
  --nano-black: #0a0e1a;
  --nano-blue-950: #0f1520;
  --nano-blue-900: #141b2e;
  --nano-blue-800: #1a2438;
  --nano-blue-700: #223047;
  --nano-blue-600: #2d4a7c;
  --nano-blue-500: #4a7bc8;
  --nano-blue-400: #6b9bd8;
  --nano-blue-300: #8bb2e8;
  --nano-blue-200: #a8c5f0;
  --nano-blue-100: #d0dff5;
  --nano-white: #ffffff;
  --bg: var(--nano-black);
  --surface: var(--nano-blue-950);
  --text-primary: #c5d4e8;
  --text-secondary: #8499b3;
  --text-muted: #5f748f;
  --divider: rgba(74, 123, 200, 0.12);
  --accent: #4a7bc8;
  --accent-bright: #6b9bd8;
  --font-sans: ui-sans-serif, system-ui, -apple-system, "SF Pro SC", "SF Pro Text", "PingFang SC", "HarmonyOS Sans SC", "Segoe UI", "Roboto", "Helvetica Neue", "Helvetica", "Arial", "Noto Sans CJK SC", "Microsoft YaHei", sans-serif;
  --fs-hero: clamp(28px, 4.2vw, 48px);
  --fs-h1: clamp(22px, 3.2vw, 36px);
  --fs-h2: clamp(18px, 2.2vw, 28px);
  --fs-body: 15.5px;
  --lh-tight: 1.25;
  --lh-normal: 1.55;
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --shadow-1: 0 0.5px 0.5px rgba(0, 0, 0, 0.5), 0 1px 2px rgba(0, 0, 0, 0.35);
  --shadow-2: 0 1px 2px rgba(0, 0, 0, 0.5), 0 4px 10px rgba(0, 0, 0, 0.35);
  --ease-out: cubic-bezier(0.2, 0, 0, 1);
  --dur-fast: 180ms;
  --dur-base: 240ms;
  --page-max: 1140px;
  --gutter: 20px;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-normal);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--dur-base) var(--ease-out);
}

a:hover {
  color: var(--nano-white);
}

.container {
  max-width: var(--page-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(12px);
  background: rgba(10, 14, 26, 0.85);
  border-bottom: 1px solid var(--divider);
  z-index: 50;
}

header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}

.brand {
  letter-spacing: 0.06em;
  font-weight: 800;
  text-transform: uppercase;
}

.brand span {
  color: var(--nano-white);
}

nav {
  display: flex;
  gap: 18px;
  font-size: 14px;
  color: var(--text-secondary);
}

.nav-links a {
  padding: 6px 0;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 100%;
  height: 1px;
  background: var(--divider);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-base) var(--ease-out);
}

.nav-links a:hover::after,
.nav-links a:focus::after {
  transform: scaleX(1);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: var(--radius-xs);
  background: var(--accent);
  color: #ffffff;
  font-weight: 600;
  transition: background var(--dur-base) var(--ease-out), transform var(--dur-fast) var(--ease-out);
}

.btn:hover {
  background: var(--accent-bright);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(74, 123, 200, 0.25);
}

.btn.ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--divider);
}

.btn.ghost:hover {
  border-color: var(--accent);
  color: var(--text-primary);
  background: rgba(74, 123, 200, 0.08);
}

.section {
  padding: 72px 0;
}

.section:not(:first-of-type) {
  border-top: 1px solid var(--divider);
}

.nano-grid {
  background-image: linear-gradient(to right, rgba(74, 123, 200, 0.06) 1px, transparent 1px), linear-gradient(to bottom, rgba(74, 123, 200, 0.06) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: center center;
}

.section h1,
.section h2 {
  margin: 0 0 16px;
}

.section h1 {
  font-size: var(--fs-hero);
  line-height: var(--lh-tight);
}

.section h2 {
  font-size: var(--fs-h1);
}

.grid-two {
  display: grid;
  gap: 32px;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.card {
  background: var(--surface);
  border: 1px solid var(--divider);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  transition: transform var(--dur-base) var(--ease-out), box-shadow var(--dur-base) var(--ease-out), border-color var(--dur-base) var(--ease-out);
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 16px rgba(74, 123, 200, 0.15);
  border-color: rgba(74, 123, 200, 0.25);
}

.list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.list li {
  color: var(--text-secondary);
}

.faq li {
  padding: 16px;
  border: 1px solid var(--divider);
  border-radius: var(--radius-xs);
  background: rgba(74, 123, 200, 0.04);
}

.placeholder {
  height: 220px;
  border: 1px dashed var(--divider);
  border-radius: var(--radius-sm);
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.split {
  display: grid;
  gap: 36px;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  align-items: start;
}

.badge {
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: 500;
}

.case-grid {
  display: grid;
  gap: 24px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.case-card {
  border: 1px solid var(--divider);
  border-radius: var(--radius-sm);
  padding: 20px;
  background: var(--surface);
  box-shadow: var(--shadow-1);
}

.case-card h3 {
  margin: 0 0 12px;
  font-size: 18px;
}

.case-card p {
  margin: 0 0 16px;
  color: var(--text-secondary);
}

.contact-list {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.contact-item {
  border: 1px solid var(--divider);
  border-radius: var(--radius-xs);
  padding: 18px;
  background: rgba(74, 123, 200, 0.04);
}

footer {
  border-top: 1px solid var(--divider);
  padding: 32px 0;
  text-align: center;
  color: var(--text-secondary);
  font-size: 14px;
}

@media (max-width: 720px) {
  header .container {
    flex-wrap: wrap;
    gap: 12px;
  }

  nav {
    order: 3;
    width: 100%;
    justify-content: space-between;
  }

  .hero-cta {
    flex-direction: column;
    align-items: flex-start;
  }
}