:root {
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, 
               Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  --text-color: #1a1a1a;
  --text-muted: #555555;
  --bg-card: rgba(255, 255, 255, 0.96);
  --border-color: #e2e8f0;
  --link-color: #1d4ed8;
  --accent-color: #0f172a;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-main);
  line-height: 1.7;
  color: var(--text-color);
  background-color: #f1f5f9;
  background-attachment: fixed;
  background-position: center top;
  background-repeat: no-repeat;
  background-size: cover;
  padding: 24px 16px;
}

.page-wrapper {
  max-width: 820px;
  margin: 0 auto;
  background: var(--bg-card);
  backdrop-filter: blur(8px);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 48px 40px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.lang-switch {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
  margin-bottom: 20px;
}

.lang-btn {
  display: inline-block;
  padding: 6px 14px;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  color: var(--text-color);
  background: #ffffff;
  transition: all 0.2s ease;
}

.lang-btn.active {
  background: var(--accent-color);
  color: #ffffff;
  border-color: var(--accent-color);
}

.lang-btn:hover:not(.active) {
  background: #f8fafc;
}

h1 {
  font-size: 2.1rem;
  line-height: 1.25;
  color: var(--accent-color);
  margin-bottom: 8px;
}

.subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  font-style: italic;
  margin-bottom: 16px;
}

.intro-lead {
  font-size: 1.05rem;
  margin-bottom: 12px;
}

.notice-box {
  background: #f8fafc;
  border-left: 4px solid var(--accent-color);
  padding: 12px 16px;
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-top: 16px;
}

hr {
  border: 0;
  border-top: 1px solid var(--border-color);
  margin: 36px 0;
}

h2 {
  font-size: 1.45rem;
  color: var(--accent-color);
  margin: 28px 0 16px;
}

h3 {
  font-size: 1.15rem;
  color: #334155;
  margin: 20px 0 10px;
}

p {
  margin-bottom: 16px;
}

ul {
  margin: 0 0 20px 24px;
}

li {
  margin-bottom: 8px;
}

a {
  color: var(--link-color);
  text-decoration: underline;
}

a:hover {
  text-decoration: none;
}

footer {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
  font-size: 0.9rem;
  color: var(--text-muted);
  font-style: italic;
}

@media (max-width: 640px) {
  body {
    padding: 12px 8px;
  }
  .page-wrapper {
    padding: 28px 18px;
  }
  h1 {
    font-size: 1.6rem;
  }
  h2 {
    font-size: 1.25rem;
  }
}
.ref-badge {
  display: inline-block;
  background-color: #f8fafc;
  color: #555555;
  font-size: 0.9em;
  padding: 1px 6px;
  border-radius: 4px;
  border: 1px solid #e2e8f0;
  vertical-align: baseline;
  white-space: normal;
}