/* ...existing styles... */
:root {
  --bg: #ffffff;
  --text: #111111;
  --muted: #666666;
  --surface: #f6f6f6;
  --border: #e6e6e6;
  --focus: #111111;
}
:root.dark {
  --bg: #0c0c0c;
  --text: #f2f2f2;
  --muted: #a0a0a0;
  --surface: #141414;
  --border: #242424;
  --focus: #f2f2f2;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Noto Sans", system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: var(--bg); border-bottom: 1px solid var(--border);
  backdrop-filter: saturate(1.2);
}
.container { max-width: 1100px; margin: 0 auto; padding: 0 16px; }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-weight: 800; text-decoration: none; color: var(--text); letter-spacing: 0.5px; }
.logo .muted { color: var(--muted); font-weight: 600; }
.nav-toggle { display: none; background: transparent; border: 1px solid var(--border); padding: 6px 10px; border-radius: 8px; color: var(--text); }
.menu { display: flex; gap: 16px; list-style: none; padding: 0; margin: 0; }
.menu a { color: var(--text); text-decoration: none; padding: 8px 10px; border-radius: 8px; }
.menu a:hover { background: var(--surface); }
.mode-toggle { border: 1px solid var(--border); background: var(--surface); color: var(--text); border-radius: 8px; padding: 8px 10px; }

/* Hero */
.hero { padding: 64px 16px 40px; }
.hero-content { max-width: 820px; }
h1 { font-size: 42px; line-height: 1.1; margin: 6px 0 10px; }
.subtitle { color: var(--muted); margin: 0 0 10px; }
.lede { font-size: 18px; margin-bottom: 18px; color: var(--text); }
.hero-actions { display: flex; gap: 12px; }
.btn { border: 1px solid var(--border); padding: 10px 14px; border-radius: 10px; text-decoration: none; color: var(--text); transition: transform 160ms ease, background 160ms ease; }
.btn:hover { transform: translateY(-1px); background: var(--surface); }
.btn.primary { border-color: var(--text); }

/* Sections */
.section { padding: 40px 16px; border-top: 1px solid var(--border); }
.section h2 { margin: 0 0 10px; font-size: 28px; }
.keypoints { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 10px; padding-left: 18px; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.card { border: 1px solid var(--border); border-radius: 12px; padding: 16px; background: var(--surface); }
.card h3 { margin-top: 0; }

/* Tabs */
.tabs { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 12px; }
.tab { border: 1px solid var(--border); background: transparent; color: var(--text); padding: 8px 12px; border-radius: 10px; cursor: pointer; }
.tab.active { border-color: var(--text); background: var(--surface); }
.tab-panels .panel { border: 1px dashed var(--border); border-radius: 12px; padding: 14px; }

/* Cases */
.cases .case-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; }
.case { border: 1px solid var(--border); border-radius: 12px; padding: 16px; background: var(--surface); }

/* Glossary */
.glossary-controls { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; }
.glossary-controls input { flex: 1; padding: 10px 12px; border: 1px solid var(--border); border-radius: 10px; background: var(--bg); color: var(--text); }
.glossary-list { display: grid; grid-template-columns: 1fr; gap: 6px; }
.glossary-list dt { font-weight: 600; }
.glossary-list dd { margin: 0 0 8px 0; color: var(--muted); }

/* Accordion */
.accordion { display: grid; gap: 8px; }
.acc-head { width: 100%; text-align: left; border: 1px solid var(--border); padding: 10px 12px; border-radius: 10px; background: var(--surface); color: var(--text); }
.acc-body { padding: 10px 12px; border-left: 2px solid var(--border); margin-left: 4px; color: var(--muted); }

/* Resources */
.resources { display: grid; gap: 8px; padding-left: 18px; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); padding: 24px 0; color: var(--muted); }

/* Back to top */
.back-to-top {
  position: fixed; right: 16px; bottom: 16px; z-index: 40;
  border: 1px solid var(--border); background: var(--surface); color: var(--text);
  border-radius: 999px; width: 44px; height: 44px;
  display: grid; place-items: center; opacity: 0; pointer-events: none; transition: opacity 160ms ease, transform 160ms ease;
}
.back-to-top.show { opacity: 1; pointer-events: auto; }
.back-to-top:hover { transform: translateY(-2px); }

/* Small screens */
@media (max-width: 860px) {
  .menu { display: none; position: absolute; top: 64px; right: 16px; background: var(--bg); border: 1px solid var(--border); border-radius: 12px; padding: 10px; flex-direction: column; width: min(90vw, 300px); }
  .menu.show { display: flex; }
  .nav-toggle { display: inline-block; }
  .hero { padding-top: 48px; }
}

/* Focus */
a:focus, button:focus, input:focus { outline: 2px dashed var(--focus); outline-offset: 2px; }
/* ...existing styles... */