:root {
  --bg: #f7f5ff;
  --surface: #ffffff;
  --text: #1d1830;
  --muted: #6f6884;
  --primary: #6d4aff;
  --secondary: #2f80ed;
  --border: #e8e3f6;
  --shadow: 0 18px 50px rgba(70, 51, 130, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, Arial, Helvetica, sans-serif;
  background:
    radial-gradient(circle at top left, rgba(109, 74, 255, 0.12), transparent 34%),
    radial-gradient(circle at top right, rgba(47, 128, 237, 0.10), transparent 30%),
    var(--bg);
  color: var(--text);
  line-height: 1.72;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.site-header {
  padding: 24px 20px 0;
}

.nav {
  max-width: 1100px;
  margin: 0 auto;
  background: rgba(255,255,255,0.86);
  border: 1px solid rgba(255,255,255,0.8);
  backdrop-filter: blur(16px);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  position: sticky;
  top: 16px;
  z-index: 10;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  font-size: 20px;
}

.brand-mark {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 22px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.nav-links a {
  padding: 9px 13px;
  border-radius: 12px;
  color: var(--text);
  font-weight: 700;
}

.nav-links a:hover {
  background: #f0ecff;
  text-decoration: none;
}

.hero {
  max-width: 1100px;
  margin: 48px auto 0;
  padding: 0 20px;
}

.hero-card {
  background: linear-gradient(135deg, #6d4aff, #2f80ed);
  border-radius: 34px;
  padding: 54px;
  box-shadow: var(--shadow);
  color: white;
}

.hero-card h1 {
  margin: 0 0 14px;
  font-size: clamp(40px, 8vw, 72px);
  line-height: 1;
  letter-spacing: -2px;
}

.hero-card p {
  margin: 0;
  max-width: 720px;
  font-size: 18px;
  color: rgba(255,255,255,0.88);
}

.content {
  max-width: 960px;
  margin: 34px auto 70px;
  padding: 0 20px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 28px;
  box-shadow: var(--shadow);
  padding: 34px;
  margin-bottom: 22px;
}

.card h1,
.card h2,
.card h3 {
  line-height: 1.25;
}

.card h1 {
  margin-top: 0;
  font-size: 40px;
  letter-spacing: -1px;
}

.card h2 {
  margin-top: 32px;
  color: var(--primary);
}

.card h3 {
  margin-top: 24px;
}

.meta {
  color: var(--muted);
  margin-bottom: 26px;
}

.notice {
  background: #f2efff;
  border-left: 5px solid var(--primary);
  padding: 18px 20px;
  border-radius: 16px;
  margin: 22px 0;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 26px;
}

.feature {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 22px;
}

.feature h3 {
  margin-top: 0;
}

.footer {
  text-align: center;
  color: var(--muted);
  padding: 0 20px 42px;
}

ul {
  padding-left: 22px;
}

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

  .hero-card {
    padding: 34px 24px;
    border-radius: 26px;
  }

  .card {
    padding: 24px;
  }

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

  .nav-links {
    width: 100%;
  }
}