* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, "Microsoft YaHei", sans-serif;
  color: #111827;
  background: linear-gradient(135deg, #f7f8fb 0%, #eef2ff 100%);
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding: 22px 7%;
  background: rgba(255, 255, 255, 0.84);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(17, 24, 39, 0.08);
  position: sticky;
  top: 0;
}

.brand {
  font-size: 24px;
  font-weight: 800;
  letter-spacing: -0.03em;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

nav a {
  color: #374151;
  text-decoration: none;
  font-size: 15px;
}

nav a:hover {
  color: #111827;
}

.container {
  width: min(1080px, 92%);
  margin: 0 auto;
  padding: 72px 0;
}

.hero {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 36px;
  align-items: center;
}

.eyebrow {
  color: #4f46e5;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 13px;
}

h1 {
  font-size: clamp(38px, 6vw, 68px);
  line-height: 1.05;
  margin: 12px 0 22px;
  letter-spacing: -0.06em;
}

h2 {
  font-size: 24px;
  margin-top: 0;
}

p, li {
  font-size: 17px;
  line-height: 1.75;
  color: #374151;
}

.lead {
  font-size: 20px;
  color: #4b5563;
}

.actions,
.download-box {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 26px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 22px;
  border-radius: 12px;
  text-decoration: none;
  font-weight: 700;
}

.primary {
  background: #111827;
  color: #ffffff;
}

.secondary {
  background: #ffffff;
  color: #111827;
  border: 1px solid rgba(17, 24, 39, 0.12);
}

.disabled {
  opacity: 0.55;
  cursor: not-allowed;
  pointer-events: none;
}

.card {
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid rgba(17, 24, 39, 0.08);
  border-radius: 24px;
  padding: 30px;
  box-shadow: 0 18px 50px rgba(17, 24, 39, 0.08);
}

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.article {
  max-width: 860px;
}

.article section {
  margin-top: 32px;
}

.note {
  font-size: 14px;
  color: #6b7280;
}

footer {
  padding: 28px 7%;
  border-top: 1px solid rgba(17, 24, 39, 0.08);
}

footer p {
  font-size: 14px;
  color: #6b7280;
}

@media (max-width: 760px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero,
  .grid {
    grid-template-columns: 1fr;
  }

  .container {
    padding: 48px 0;
  }
}