/* Colossus, explicado — inspirado en la sobriedad de grok.com
   (fondo cálido muy oscuro, tipografía grande, mucho aire, contraste alto).
   No usa tipografías, logos ni marcas de xAI o Grok. */

:root {
  --bg: #0a0a09;
  --bg-soft: #111110;
  --bg-card: #161614;
  --bg-card-hover: #1c1c19;
  --text: #f4f3ef;
  --muted: rgba(244, 243, 239, 0.62);
  --dim: rgba(244, 243, 239, 0.42);
  --line: rgba(255, 255, 255, 0.1);
  --line-strong: rgba(255, 255, 255, 0.18);
  --ivory: #e8e2d4;
  --ivory-dim: rgba(232, 226, 212, 0.14);
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
  --radius: 18px;
  --font:
    "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto,
    sans-serif;
  --max: 1120px;
  --pad: clamp(1.25rem, 4vw, 2.5rem);
  --header-h: 4.25rem;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  color-scheme: dark;
}
html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
}
body {
  font-family: var(--font);
  font-weight: 400;
  font-size: 1.0625rem;
  line-height: 1.6;
  letter-spacing: -0.011em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img,
picture {
  display: block;
  max-width: 100%;
  height: auto;
}
a {
  color: var(--ivory);
  text-underline-offset: 0.18em;
}
a:hover {
  color: #fff;
}
:focus-visible {
  outline: 2px solid var(--ivory);
  outline-offset: 3px;
}
::selection {
  background: rgba(232, 226, 212, 0.28);
  color: #fff;
}

.skip {
  position: absolute;
  left: 1rem;
  top: -4rem;
  background: var(--text);
  color: var(--bg);
  padding: 0.6rem 1rem;
  border-radius: 8px;
  z-index: 100;
}
.skip:focus {
  top: 0.75rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--header-h);
  display: flex;
  align-items: center;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  background: rgba(10, 10, 9, 0.72);
  border-bottom: 1px solid transparent;
  transition:
    background 0.3s ease,
    border-color 0.3s ease;
}
.site-header.is-solid {
  background: rgba(10, 10, 9, 0.92);
  border-bottom-color: var(--line);
}
.header-inner {
  width: min(var(--max), 100%);
  margin: 0 auto;
  padding: 0 var(--pad);
  display: flex;
  align-items: center;
  gap: 1rem;
}
.brand {
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  letter-spacing: 0.14em;
  font-size: 0.78rem;
  text-transform: uppercase;
}
.brand:hover {
  color: var(--text);
}
.badge {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--line-strong);
  color: var(--muted);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.28rem 0.55rem;
  border-radius: 999px;
  white-space: nowrap;
}
.nav {
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.15rem 1.1rem;
}
.nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
}
.nav a:hover {
  color: var(--text);
}

/* Hero */
.hero {
  position: relative;
  min-height: calc(100svh - var(--header-h));
  display: flex;
  align-items: flex-end;
  isolation: isolate;
  overflow: hidden;
}
.hero-media {
  position: absolute;
  inset: 0;
  z-index: -2;
}
.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  transform: scale(1.04);
  filter: saturate(0.7) contrast(1.05) brightness(0.72);
}
.hero-shade {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(
      180deg,
      rgba(10, 10, 9, 0.35) 0%,
      rgba(10, 10, 9, 0.2) 35%,
      rgba(10, 10, 9, 0.82) 70%,
      var(--bg) 100%
    ),
    linear-gradient(
      90deg,
      rgba(10, 10, 9, 0.55) 0%,
      rgba(10, 10, 9, 0.15) 55%,
      rgba(10, 10, 9, 0.45) 100%
    );
}
.hero-inner {
  width: min(var(--max), 100%);
  margin: 0 auto;
  padding: clamp(4rem, 12vh, 7rem) var(--pad) clamp(3rem, 8vh, 5rem);
}
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--muted);
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin: 0 0 1.1rem;
}
.kicker::before {
  content: "";
  width: 1.6rem;
  height: 1px;
  background: var(--ivory);
  opacity: 0.7;
}
.hero h1 {
  font-weight: 500;
  font-size: clamp(3.2rem, 11vw, 8.2rem);
  line-height: 0.92;
  letter-spacing: -0.05em;
  margin: 0 0 1.25rem;
}
.lede {
  max-width: 36rem;
  font-size: clamp(1.05rem, 2.2vw, 1.28rem);
  line-height: 1.5;
  color: var(--muted);
  margin: 0 0 2rem;
  font-weight: 400;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem 1rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  padding: 0.8rem 1.25rem;
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition:
    transform 0.2s ease,
    background 0.2s ease,
    border-color 0.2s ease;
}
.btn-primary {
  background: var(--text);
  color: #111;
}
.btn-primary:hover {
  background: #fff;
  color: #111;
  transform: translateY(-1px);
}
.btn-ghost {
  border: 1px solid var(--line-strong);
  color: var(--text);
  background: rgba(255, 255, 255, 0.03);
}
.btn-ghost:hover {
  border-color: var(--text);
  color: var(--text);
}

/* Sections */
.wrap {
  width: min(var(--max), 100%);
  margin: 0 auto;
  padding: 0 var(--pad);
}
section {
  padding: clamp(4rem, 10vw, 7.5rem) 0;
}
.section-label {
  color: var(--dim);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin: 0 0 0.85rem;
}
h2 {
  font-size: clamp(1.9rem, 4.4vw, 3.15rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.12;
  margin: 0 0 1.25rem;
}
.prose {
  max-width: 40rem;
  color: var(--muted);
}
.prose p {
  margin: 0 0 1rem;
}
.prose p:last-child {
  margin-bottom: 0;
}

.split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
}
@media (min-width: 860px) {
  .split {
    grid-template-columns: 1.05fr 0.95fr;
  }
}

.frame {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-card);
  box-shadow: var(--shadow);
}
.frame img {
  width: 100%;
  height: auto;
  object-fit: cover;
}
.caption {
  margin: 0.7rem 0 0;
  font-size: 0.78rem;
  line-height: 1.45;
  color: var(--dim);
}
.caption a {
  color: var(--muted);
}

/* Cards */
.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 2.4rem;
}
@media (min-width: 640px) {
  .cards {
    grid-template-columns: 1fr 1fr;
  }
}
@media (min-width: 960px) {
  .cards {
    grid-template-columns: repeat(3, 1fr);
  }
  .cards .card:nth-child(4),
  .cards .card:nth-child(5) {
    grid-column: span 1;
  }
  .cards {
    grid-template-columns: repeat(6, 1fr);
  }
  .cards .card {
    grid-column: span 2;
  }
  .cards .card:nth-child(4) {
    grid-column: 2 / span 2;
  }
  .cards .card:nth-child(5) {
    grid-column: 4 / span 2;
  }
}
.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.45rem 1.35rem 1.5rem;
  transition:
    transform 0.35s ease,
    border-color 0.35s ease,
    background 0.35s ease;
}
.card:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  background: var(--bg-card-hover);
}
.card-icon {
  width: 2.15rem;
  height: 2.15rem;
  border-radius: 9px;
  border: 1px solid var(--line-strong);
  display: grid;
  place-items: center;
  margin-bottom: 1rem;
  color: var(--ivory);
  background: var(--ivory-dim);
}
.card-icon svg {
  width: 1.1rem;
  height: 1.1rem;
}
.card h3 {
  margin: 0 0 0.55rem;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

/* Mid images */
.media-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-top: 3.2rem;
}
@media (min-width: 800px) {
  .media-row {
    grid-template-columns: 1.1fr 0.9fr;
  }
}

/* Stats */
.stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 22px;
  overflow: hidden;
  margin-top: 2.2rem;
}
@media (min-width: 800px) {
  .stats {
    grid-template-columns: repeat(4, 1fr);
  }
}
.stat {
  background: var(--bg-soft);
  padding: 1.6rem 1.15rem 1.45rem;
  min-height: 9.2rem;
}
.stat-value {
  font-size: clamp(1.7rem, 3.6vw, 2.45rem);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1.05;
  font-variant-numeric: tabular-nums;
  margin: 0 0 0.45rem;
}
.stat-value .unit {
  display: inline-block;
  margin-left: 0.2em;
  font-size: 0.48em;
  letter-spacing: -0.02em;
  color: var(--muted);
  font-weight: 500;
}
.stat p:not(.stat-value) {
  margin: 0;
  color: var(--dim);
  font-size: 0.82rem;
  line-height: 1.4;
}
.stat-value {
  color: var(--text);
}
section[id] {
  scroll-margin-top: calc(var(--header-h) + 0.75rem);
}

/* Video fallback */
.video-box {
  margin-top: 1.8rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    radial-gradient(1200px 300px at 20% 0%, var(--ivory-dim), transparent 60%),
    var(--bg-card);
  padding: clamp(1.5rem, 4vw, 2.4rem);
}
.video-box p {
  color: var(--muted);
  margin: 0 0 1.1rem;
  max-width: 44rem;
}
.video-box .note {
  font-size: 0.9rem;
  color: var(--dim);
}

/* Sources */
.sources,
.credits {
  list-style: none;
  margin: 0;
  padding: 0;
}
.sources li,
.credits li {
  padding: 0.95rem 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.95rem;
}
.sources li:last-child,
.credits li:last-child {
  border-bottom: 1px solid var(--line);
}
.sources strong,
.credits strong {
  color: var(--text);
  font-weight: 500;
}

/* Footer */
footer {
  border-top: 1px solid var(--line);
  padding: 2.2rem 0 3rem;
  color: var(--dim);
  font-size: 0.88rem;
}
.footer-inner {
  width: min(var(--max), 100%);
  margin: 0 auto;
  padding: 0 var(--pad);
  display: grid;
  gap: 0.7rem;
}
footer .badge {
  width: max-content;
}

/* Reveal */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  animation: none;
}
.reveal.is-in {
  animation: rise 0.85s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(22px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal,
  .reveal.is-in {
    opacity: 1;
    transform: none;
    animation: none;
  }
  .card:hover {
    transform: none;
  }
  .hero-media img {
    transform: none;
  }
}

@media (max-width: 639px) {
  .nav {
    display: none;
  }
  .hero h1 {
    font-size: clamp(2.8rem, 16vw, 4.4rem);
  }
  .stat {
    min-height: 8rem;
    padding: 1.2rem 0.9rem 1.15rem;
  }
}

.noise {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 80;
  opacity: 0.035;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 1  0 0 0 0 1  0 0 0 0 1  0 0 0 0.7 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
}