:root {
  color-scheme: dark;
  --background: #0a0a0a;
  --foreground: #f4f4f5;
  --muted: #a1a1aa;
  --accent: #5e6ad2;
  --accent-text: #8b93ea; /* #5e6ad2 is 4.21:1 on #0a0a0a at 12px */
  --accent-hot: #8b7ff0;
  --hairline: rgba(255, 255, 255, 0.1);
  --surface-1: #17171d;
  --ease-ui: cubic-bezier(0.4, 0, 0.2, 1);
  --dur-ui: 150ms;
  --max: 1100px;
  --gutter: 6vw;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--background);
  color: var(--foreground);
  font-family: Geist, ui-sans-serif, system-ui, sans-serif;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

.skip {
  position: absolute;
  left: 1rem;
  top: 0;
  z-index: 20;
  transform: translateY(-120%);
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  font-size: 0.875rem;
  padding: 0.75rem 1rem;
  border-radius: 0 0 10px 10px;
  text-decoration: none;
}

.skip:focus {
  transform: translateY(0);
}

.hero {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: 1.5rem var(--gutter) 1.75rem;
  overflow: hidden;
}

.hero-glow {
  pointer-events: none;
  position: absolute;
  top: -8rem;
  right: -4rem;
  width: 28rem;
  height: 28rem;
  background: radial-gradient(
    closest-side,
    color-mix(in srgb, var(--accent) 28%, transparent),
    transparent 70%
  );
}

.topbar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
  font-weight: 500;
  letter-spacing: -0.02em;
  min-height: 44px;
}

.wordmark .mark {
  color: var(--accent);
  flex-shrink: 0;
}

.topbar-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1rem;
}

.topbar-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.875rem;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.topbar-links a:hover {
  color: var(--foreground);
}

.eyebrow {
  position: relative;
  margin: 0;
  color: var(--accent-text);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1 {
  position: relative;
  font-family: "Instrument Serif", ui-serif, Georgia, serif;
  font-weight: 400;
  font-size: clamp(2.125rem, 6vw, 3.5rem);
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin: 0.65rem 0 1rem;
}

.lede {
  position: relative;
  margin: 0;
  color: var(--muted);
  max-width: 62ch;
  font-size: 1.05rem;
  line-height: 1.65;
}

.chips {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  padding: 0;
  margin: 1.35rem 0 0;
}

.chips li {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: #d4d4d8;
  border: 1px solid var(--hairline);
  background: color-mix(in srgb, var(--surface-1) 80%, transparent);
  border-radius: 999px;
  padding: 0.4rem 0.75rem;
}

.actions {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 44px;
  padding: 0.65rem 1.05rem;
  border-radius: 10px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  transition:
    border-color var(--dur-ui) var(--ease-ui),
    background var(--dur-ui) var(--ease-ui),
    transform var(--dur-ui) var(--ease-ui);
}

.btn.primary {
  color: #fff;
  background: var(--accent);
  box-shadow: 0 10px 28px color-mix(in srgb, var(--accent) 32%, transparent);
}

.btn.primary:hover {
  background: color-mix(in srgb, var(--accent) 86%, white);
}

.btn.ghost {
  color: #d4d4d8;
  border: 1px solid var(--hairline);
}

.btn.ghost:hover {
  border-color: color-mix(in srgb, var(--accent) 55%, transparent);
  color: var(--foreground);
}

.btn:active {
  transform: scale(0.98);
}

.toc {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0.65rem var(--gutter);
  background: color-mix(in srgb, var(--background) 78%, transparent);
  backdrop-filter: blur(20px) saturate(1.6);
  -webkit-backdrop-filter: blur(20px) saturate(1.6);
  border-bottom: 1px solid var(--hairline);
}

.toc a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 0.95rem;
  color: #d4d4d8;
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  border: 1px solid var(--hairline);
  border-radius: 999px;
  cursor: pointer;
  transition:
    border-color var(--dur-ui) var(--ease-ui),
    color var(--dur-ui) var(--ease-ui),
    background var(--dur-ui) var(--ease-ui);
}

.toc a:hover {
  border-color: color-mix(in srgb, var(--accent) 70%, transparent);
  color: #fff;
}

body:has(#landing:target) .toc a[href="#landing"],
body:has(#chat:target) .toc a[href="#chat"],
body:has(#missions:target) .toc a[href="#missions"],
body:has(#evals:target) .toc a[href="#evals"] {
  color: #fff;
  background: color-mix(in srgb, var(--accent) 18%, transparent);
  border-color: color-mix(in srgb, var(--accent) 70%, transparent);
}

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

figure {
  margin: 0 auto 3.5rem;
  padding: 0 var(--gutter);
  scroll-margin-top: 5.5rem;
}

figure:target img {
  border-color: color-mix(in srgb, var(--accent) 50%, transparent);
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.45),
    0 0 0 1px color-mix(in srgb, var(--accent) 35%, transparent);
}

figure img {
  width: 100%;
  border-radius: 16px;
  border: 1px solid var(--hairline);
  background: var(--surface-1);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.45);
}

figcaption {
  color: var(--muted);
  font-size: 0.9375rem;
  margin-top: 0.85rem;
  line-height: 1.6;
  max-width: 72ch;
}

figcaption strong {
  color: var(--foreground);
  font-weight: 600;
}

figcaption em {
  font-style: italic;
}

.step {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.25rem;
  margin: 0.85rem 0 0;
  font-size: 0.8125rem;
  color: var(--muted);
}

.step a {
  color: var(--accent-hot);
  text-decoration: none;
  font-weight: 600;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.step a:hover {
  text-decoration: underline;
}

.step span {
  font-variant-numeric: tabular-nums;
}

footer {
  color: var(--muted);
  text-align: center;
  padding: 1.5rem var(--gutter) 4rem;
  font-size: 0.8125rem;
  line-height: 1.6;
}

footer p {
  margin: 0 0 0.5rem;
  max-width: 62ch;
  margin-left: auto;
  margin-right: auto;
}

footer a {
  color: color-mix(in srgb, var(--accent) 70%, white);
}

footer code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.78em;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

@media (max-width: 640px) {
  .hero {
    padding-top: 1rem;
  }

  .topbar {
    margin-bottom: 1.75rem;
  }

  h1 {
    font-size: 2rem;
  }

  .lede {
    font-size: 1rem;
  }

  figure {
    margin-bottom: 2.5rem;
  }

  figure img {
    border-radius: 12px;
  }
}

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

  .btn,
  .toc a {
    transition: none;
  }

  .btn:active {
    transform: none;
  }

  .hero-glow {
    display: none;
  }
}