/* Reset-ish */
* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif; color: #0f172a; background: radial-gradient(1200px 600px at 20% -10%, #dbeafe 0%, rgba(219,234,254,0) 50%), radial-gradient(900px 500px at 120% -20%, #fce7f3 0%, rgba(252,231,243,0) 50%), #ffffff; overflow-x: hidden; }

:root {
  --primary: #4f46e5;
  --primary-900: #312e81;
  --ai: #0ea5e9;
  --human: #22c55e;
  --text-muted: #475569;
  --panel: rgba(255,255,255,0.7);
  --border: rgba(15, 23, 42, 0.08);
  --shadow: 0 10px 30px rgba(2,6,23,0.08), 0 2px 8px rgba(2,6,23,0.05);
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }

.site-header { position: sticky; top: 0; backdrop-filter: saturate(180%) blur(16px); background: rgba(255,255,255,0.7); border-bottom: 1px solid var(--border); z-index: 10; }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: -0.02em; }
.logo { font-size: 22px; }
.brand-text { font-size: 18px; }
.nav { display: flex; gap: 16px; }
.nav-link { color: #0f172a; text-decoration: none; font-weight: 500; padding: 8px 10px; border-radius: 8px; }
.nav-link:hover { background: rgba(15, 23, 42, 0.06); }
.nav-link.active { color: var(--primary); background: rgba(79, 70, 229, 0.08); }

.main { padding: 40px 0 60px; }
.hero { text-align: center; margin-bottom: 24px; }
.hero.small { margin-bottom: 8px; }
.title { font-size: clamp(28px, 5vw, 42px); margin: 0 0 6px; letter-spacing: -0.02em; text-wrap: balance; }
.subtitle { color: var(--text-muted); margin: 0; }

.cards { display: grid; grid-template-columns: 1fr; gap: 16px; margin: 24px 0; }
@media (min-width: 880px) { .cards { grid-template-columns: 1.3fr 1fr; } }

.callout { margin: 16px 0 8px; padding: 14px 18px; border-radius: 12px; border: 1px solid rgba(244, 114, 182, 0.4); background: rgba(244, 114, 182, 0.12); color: #9d174d; display: flex; align-items: flex-start; gap: 12px; }
.callout strong { color: #be123c; }
.callout-icon { font-size: 20px; line-height: 1; }

.card { background: var(--panel); border: 1px solid var(--border); border-radius: 16px; padding: 18px; box-shadow: var(--shadow); }
.card.focus { display: grid; grid-template-columns: 1fr; gap: 12px; align-items: center; }
@media (min-width: 540px) { .card.focus { grid-template-columns: 1fr auto; } }
.legend { display: flex; gap: 16px; align-items: center; justify-content: center; }
.legend-item { display: flex; gap: 8px; align-items: center; color: var(--text-muted); }
.dot { width: 10px; height: 10px; border-radius: 50%; display: inline-block; }
.dot.ai { background: var(--ai); }
.dot.human { background: var(--human); }

.stats { display: grid; grid-template-columns: 1fr; gap: 12px; align-items: center; }
/* Medium: three columns without dividers to avoid overflow */
@media (min-width: 680px) { .stats { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
/* Large: five columns (with divider rails) */
@media (min-width: 1100px) { .stats { grid-template-columns: 1fr auto 1fr auto 1fr; } }
.stat { text-align: center; min-width: 0; }
.stat-label { color: var(--text-muted); font-size: 14px; }
.stat-number { font-weight: 800; font-size: clamp(20px, 3.2vw, 32px); line-height: 1.12; letter-spacing: -0.02em; white-space: nowrap; overflow-wrap: normal; }
.divider { width: 1px; height: 40px; background: var(--border); margin: 0 auto; display: none; }
@media (min-width: 1100px) { .divider { display: block; } }

.ring { position: relative; width: 260px; height: 260px; margin: 0 auto; }
.ring-svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.ring-bg { fill: none; stroke: rgba(15, 23, 42, 0.08); stroke-width: 12; }
.ring-fg { fill: none; stroke: conic-gradient(var(--ai), var(--ai)); stroke: var(--ai); stroke-linecap: round; stroke-width: 12; stroke-dasharray: 339.292; stroke-dashoffset: 339.292; transition: stroke-dashoffset 1.2s ease-in-out; }
.ring-center { position: absolute; inset: 0; display: grid; place-items: center; }
.ring-number { font-size: 44px; font-weight: 800; letter-spacing: -0.02em; }
.ring-label { color: var(--text-muted); font-weight: 600; }

.panel { background: var(--panel); border: 1px solid var(--border); border-radius: 16px; padding: 18px; box-shadow: var(--shadow); margin: 16px 0; }
.panel-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 8px; flex-wrap: wrap; }
.pill { background: rgba(79, 70, 229, 0.09); color: var(--primary-900); padding: 6px 10px; border-radius: 999px; font-weight: 600; font-size: 12px; }
.notes { color: var(--text-muted); font-size: 14px; }
.bullets { margin: 0; padding-left: 18px; color: var(--text-muted); }
.bullets li { margin: 8px 0; }

.site-footer { margin-top: 36px; border-top: 1px solid var(--border); }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 70px; color: var(--text-muted); }
.footer-links a { color: var(--text-muted); text-decoration: none; margin-left: 14px; }
.footer-links a:hover { color: #0f172a; }

code { background: rgba(2,6,23,0.06); padding: 2px 6px; border-radius: 6px; }

/* Light dark-mode preference */
@media (prefers-color-scheme: dark) {
  body { color: #e5e7eb; background: radial-gradient(1200px 600px at 20% -10%, rgba(59,130,246,0.15) 0%, rgba(2,6,23,0) 50%), radial-gradient(900px 500px at 120% -20%, rgba(236,72,153,0.14) 0%, rgba(2,6,23,0) 50%), #0b1020; }
  .site-header { background: rgba(15, 23, 42, 0.6); border-color: rgba(255,255,255,0.08); }
  .nav-link { color: #e5e7eb; }
  .nav-link:hover { background: rgba(255,255,255,0.06); }
  .nav-link.active { background: rgba(79, 70, 229, 0.2); }
  .card, .panel { background: rgba(15, 23, 42, 0.6); border-color: rgba(255,255,255,0.08); }
  .divider { background: rgba(255,255,255,0.08); }
  .ring-bg { stroke: rgba(255,255,255,0.12); }
  .pill { color: #c7d2fe; }
  .footer-inner { color: #93c5fd; }
  .footer-links a { color: #93c5fd; }
  .callout { background: rgba(219, 39, 119, 0.18); border-color: rgba(244, 114, 182, 0.5); color: #fda4af; }
  .callout strong { color: #f472b6; }
}