:root {
  color-scheme: light;
  --bg: #ffffff;
  --page: #ffffff;
  --text: #24292f;
  --muted: #57606a;
  --border: #d0d7de;
  --border-soft: #d8dee4;
  --link: #0969da;
  --surface: #f6f8fa;
  --surface-strong: #eef2f6;
  --shadow: 0 12px 30px rgba(31, 35, 40, 0.06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Arial, sans-serif;
  font-size: 16px;
  line-height: 1.55;
}

.page-shell {
  max-width: 980px;
  margin: 0 auto;
  padding: 40px 24px 72px;
}

.document-card {
  padding: 40px;
  background: var(--page);
  border: 1px solid var(--border-soft);
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.document-title {
  margin-top: 0 !important;
  font-size: 2.1rem !important;
  letter-spacing: -0.02em;
}

.toc {
  margin: 24px 0 32px;
  padding: 18px 20px;
  background: var(--surface);
  border: 1px solid var(--border-soft);
  border-radius: 10px;
}

.toc h2 {
  margin: 0 0 10px !important;
  padding: 0 !important;
  border: 0 !important;
  font-size: 1rem !important;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.toc ol {
  margin: 0;
  padding-left: 1.5em;
}

.toc li { margin: 0.35em 0; }

.markdown-body { word-wrap: break-word; }

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4,
.markdown-body h5,
.markdown-body h6 {
  margin-top: 28px;
  margin-bottom: 14px;
  font-weight: 700;
  line-height: 1.25;
  scroll-margin-top: 24px;
}

.markdown-body h1 {
  padding-bottom: 0.35em;
  font-size: 1.85rem;
  border-bottom: 1px solid var(--border-soft);
}

.markdown-body h2 {
  padding-bottom: 0.25em;
  font-size: 1.35rem;
  border-bottom: 1px solid var(--border-soft);
}

.markdown-body h3 { font-size: 1.12rem; }
.markdown-body h4 { font-size: 1rem; }

.markdown-body p {
  margin-top: 0;
  margin-bottom: 14px;
}

.markdown-body a {
  color: var(--link);
  text-decoration: none;
}

.markdown-body a:hover { text-decoration: underline; }

.markdown-body ul,
.markdown-body ol {
  margin-top: 0;
  margin-bottom: 16px;
  padding-left: 1.75em;
}

.markdown-body li { margin: 0.35em 0; }

.markdown-body strong { font-weight: 700; }

.meta-line {
  color: var(--muted);
  font-size: 0.95rem;
}

.important {
  padding: 10px 12px;
  background: var(--surface);
  border-left: 4px solid var(--border);
  border-radius: 6px;
}

.label {
  font-weight: 700;
}

@media (max-width: 700px) {
  body { font-size: 15px; }
  .page-shell { padding: 18px 12px 48px; }
  .document-card {
    padding: 24px 18px;
    border-radius: 0;
    border-left: 0;
    border-right: 0;
  }
  .document-title { font-size: 1.75rem !important; }
  .markdown-body h1 { font-size: 1.55rem; }
  .markdown-body h2 { font-size: 1.22rem; }
}