:root {
  --primary: #1565c0;
  --primary-dark: #0d47a1;
  --text: #1f2937;
  --muted: #6b7280;
  --surface: #ffffff;
  --background: #f5f7fb;
  --border: #dbe3ec;
  --danger: #b91c1c;
  font-family: Arial, Helvetica, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--background);
  color: var(--text);
  line-height: 1.6;
}

a {
  color: var(--primary);
}

header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.nav {
  max-width: 1040px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  text-decoration: none;
  font-size: 1.1rem;
  font-weight: 700;
}

.brand img {
  width: 44px;
  height: 44px;
  object-fit: contain;
}

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

.nav-links a {
  text-decoration: none;
  font-weight: 600;
}

main {
  max-width: 880px;
  margin: 0 auto;
  padding: 56px 24px;
}

.hero {
  text-align: center;
  padding: 24px 0 48px;
}

.hero img {
  width: 140px;
  max-width: 45vw;
}

.hero h1 {
  margin: 20px 0 12px;
  font-size: clamp(2rem, 5vw, 3.4rem);
  line-height: 1.15;
}

.hero p {
  max-width: 680px;
  margin: 0 auto;
  color: var(--muted);
  font-size: 1.1rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 28px;
  margin-bottom: 24px;
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.05);
}

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

.card h1 {
  margin-top: 0;
}

.button {
  display: inline-block;
  background: var(--primary);
  color: #ffffff;
  text-decoration: none;
  font-weight: 700;
  padding: 12px 18px;
  border-radius: 10px;
}

.button:hover {
  background: var(--primary-dark);
}

.notice {
  border-left: 4px solid var(--primary);
  background: #eef6ff;
  padding: 16px 18px;
  border-radius: 8px;
}

.warning {
  border-left-color: var(--danger);
  background: #fff1f2;
}

.small {
  color: var(--muted);
  font-size: 0.94rem;
}

footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  margin-top: 48px;
}

.footer-inner {
  max-width: 1040px;
  margin: 0 auto;
  padding: 24px;
  color: var(--muted);
  font-size: 0.92rem;
  text-align: center;
}

@media (max-width: 700px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav-links {
    gap: 12px;
  }

  main {
    padding-top: 32px;
  }

  .card {
    padding: 22px;
  }
}