:root {
  --color-text: #1a1a1a;
  --color-bg: #ffffff;
  --color-link: #0b4f6c;
  --color-link-hover: #083d54;
  --color-border: #d0d7de;
  --color-accent: #0b4f6c;
  --color-green: #1b6b3a;
  --color-amber: #8a5a00;
  --color-red: #9b1c1c;
  --color-muted: #4a5568;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "Cascadia Code", "Source Code Pro", Menlo, Consolas, monospace;
  --max-width: 48rem;
  --focus-ring: 3px solid #0b4f6c;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

.skip-link {
  position: absolute;
  top: -3rem;
  left: 1rem;
  padding: 0.5rem 1rem;
  background: var(--color-accent);
  color: #fff;
  z-index: 100;
  text-decoration: none;
  border-radius: 0.25rem;
}

.skip-link:focus {
  top: 1rem;
  outline: var(--focus-ring);
  outline-offset: 2px;
}

.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 1.5rem;
  background: #f8fafc;
}

.site-header-top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.25rem;
  margin-bottom: 0.75rem;
}

.site-brand {
  display: inline-block;
  line-height: 0;
}

.site-brand img {
  display: block;
  height: 2rem;
  width: auto;
}

.site-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
}

.site-header nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
}

.site-header nav a {
  display: inline-block;
  min-height: 24px;
  min-width: 24px;
  padding: 0.35rem 0.25rem;
  line-height: 1.4;
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

.site-header nav a:hover,
.site-header nav a:focus {
  color: var(--color-link-hover);
}

.site-header nav a:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 2px;
}

.site-footer a {
  display: inline-block;
  min-height: 24px;
  min-width: 24px;
  padding: 0.25rem 0.15rem;
}

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

h1, h2, h3, h4 {
  line-height: 1.25;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

h1 { font-size: 2rem; margin-top: 0; }
h2 { font-size: 1.5rem; border-bottom: 1px solid var(--color-border); padding-bottom: 0.25rem; }
h3 { font-size: 1.25rem; }

p { margin: 0 0 1rem; }

a {
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 0.15em;
  display: inline-block;
  min-height: 24px;
  line-height: 1.5;
  padding-block: 0.15rem;
}

a:hover { color: var(--color-link-hover); }
a:focus-visible { outline: var(--focus-ring); outline-offset: 2px; }

ul, ol { margin: 0 0 1rem; padding-left: 1.5rem; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0 1.5rem;
  font-size: 0.95rem;
}

caption {
  caption-side: top;
  text-align: left;
  font-weight: 600;
  padding: 0.5rem 0;
}

th, td {
  border: 1px solid var(--color-border);
  padding: 0.5rem 0.75rem;
  text-align: left;
  vertical-align: top;
}

th {
  background: #f1f5f9;
  font-weight: 600;
}

blockquote {
  margin: 1rem 0;
  padding: 0.75rem 1rem;
  border-left: 4px solid var(--color-accent);
  background: #f8fafc;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: #f1f5f9;
  padding: 0.1em 0.3em;
  border-radius: 0.2em;
}

pre {
  background: #f1f5f9;
  padding: 1rem;
  overflow-x: auto;
  border-radius: 0.25rem;
  font-size: 0.9rem;
}

pre code { background: none; padding: 0; }

.note, .warning, .synthetic-label {
  padding: 0.75rem 1rem;
  margin: 1rem 0;
  border-radius: 0.25rem;
  border: 1px solid var(--color-border);
}

.synthetic-label {
  background: #fff8e6;
  border-color: #d4a017;
}

.synthetic-label strong::before {
  content: "⚠ ";
}

.note { background: #f0f7ff; }
.warning { background: #fef2f2; border-color: #fca5a5; }

.lang-notice {
  background: #f0f7ff;
  border: 1px solid var(--color-border);
  padding: 0.75rem 1rem;
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.decision-green { border-left: 4px solid var(--color-green); padding-left: 0.75rem; }
.decision-amber { border-left: 4px solid var(--color-amber); padding-left: 0.75rem; }
.decision-red { border-left: 4px solid var(--color-red); padding-left: 0.75rem; }

.slide-nav {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.slide-nav button {
  font: inherit;
  padding: 0.5rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 0.25rem;
  background: #f8fafc;
  cursor: pointer;
}

.slide-nav button:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 2px;
}

.slide-nav button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.slide-deck .slide {
  border: 1px solid var(--color-border);
  border-radius: 0.5rem;
  padding: 1.5rem;
  margin: 1.5rem 0;
  min-height: 12rem;
  page-break-after: always;
}

.slide-deck .slide[hidden] {
  display: none;
}

.slide-deck .slide-number {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: 0.5rem;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 1.5rem;
  text-align: center;
  font-size: 0.9rem;
  color: var(--color-muted);
  background: #f8fafc;
}

@media print {
  .skip-link, .site-header nav, .lang-notice { display: none; }
  .slide-deck .slide { page-break-after: always; border: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}