/*
  neural.ai — Frontier Intelligence landing.
  Backdrop: twilight sky, horizon glow, slow aurora ribbons, sparse stars, perspective grid.
*/

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

html {
  color-scheme: dark;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  min-height: 100vh;
  background: #030811;
}

.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(32px, 8vw, 96px);
  overflow: hidden;
  isolation: isolate;
}

.hero__layer {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.hero__layer--depth {
  background:
    radial-gradient(ellipse 95% 75% at 50% -22%, rgba(56, 73, 105, 0.42) 0%, transparent 58%),
    radial-gradient(ellipse 65% 45% at 85% 108%, rgba(4, 24, 38, 0.92) 0%, transparent 52%),
    linear-gradient(188deg, #010205 0%, #030811 30%, #072032 56%, #051018 100%);
}

.hero__layer--horizon {
  background: linear-gradient(
    to bottom,
    transparent 0%,
    transparent 46%,
    rgba(56, 189, 248, 0.045) 56%,
    rgba(167, 139, 250, 0.055) 61%,
    rgba(45, 212, 191, 0.04) 68%,
    transparent 80%
  );
}

.hero__layer--ribbons {
  inset: -28% -55% 0;
  overflow: hidden;
}

.hero__ribbon {
  position: absolute;
  left: -18%;
  width: 136%;
  height: clamp(72px, 16vmin, 140px);
  border-radius: 50%;
  filter: blur(52px);
  opacity: 0.58;
  transform: rotate(-2.2deg) translateZ(0);
  will-change: transform;
}

.hero__ribbon:nth-child(1) {
  top: 46%;
  background: linear-gradient(
    92deg,
    transparent 0%,
    rgba(45, 212, 191, 0.38) 22%,
    rgba(56, 189, 248, 0.32) 48%,
    rgba(167, 139, 250, 0.26) 74%,
    transparent 100%
  );
  animation: ribbonShiftA 42s ease-in-out infinite;
}

.hero__ribbon--mid {
  top: 53%;
  height: clamp(52px, 11vmin, 100px);
  opacity: 0.42;
  background: linear-gradient(
    92deg,
    transparent 8%,
    rgba(129, 140, 248, 0.34) 42%,
    rgba(34, 211, 238, 0.22) 58%,
    transparent 94%
  );
  animation: ribbonShiftB 56s ease-in-out infinite;
}

.hero__ribbon--deep {
  top: 60%;
  height: clamp(40px, 8vmin, 76px);
  opacity: 0.32;
  background: linear-gradient(
    92deg,
    transparent 0%,
    rgba(52, 211, 153, 0.28) 48%,
    transparent 100%
  );
  animation: ribbonShiftC 48s ease-in-out infinite;
}

.hero__layer--stars {
  opacity: 0.52;
  background-image:
    radial-gradient(1px 1px at 8% 16%, rgba(255, 255, 255, 0.48), transparent),
    radial-gradient(1px 1px at 23% 41%, rgba(255, 255, 255, 0.22), transparent),
    radial-gradient(1px 1px at 91% 19%, rgba(255, 255, 255, 0.42), transparent),
    radial-gradient(1px 1px at 74% 12%, rgba(255, 255, 255, 0.18), transparent),
    radial-gradient(1px 1px at 54% 36%, rgba(255, 255, 255, 0.34), transparent),
    radial-gradient(1px 1px at 39% 13%, rgba(255, 255, 255, 0.2), transparent),
    radial-gradient(1px 1px at 84% 46%, rgba(255, 255, 255, 0.26), transparent),
    radial-gradient(1px 1px at 16% 58%, rgba(255, 255, 255, 0.16), transparent),
    radial-gradient(1px 1px at 67% 69%, rgba(255, 255, 255, 0.14), transparent),
    radial-gradient(1.5px 1.5px at 49% 26%, rgba(200, 228, 255, 0.5), transparent),
    radial-gradient(1px 1px at 31% 84%, rgba(255, 255, 255, 0.12), transparent),
    radial-gradient(1px 1px at 96% 74%, rgba(255, 255, 255, 0.2), transparent),
    radial-gradient(1px 1px at 62% 22%, rgba(255, 255, 255, 0.18), transparent),
    radial-gradient(1px 1px at 12% 33%, rgba(255, 255, 255, 0.14), transparent);
  mask-image: radial-gradient(ellipse 88% 78% at 50% 32%, #000 12%, transparent 72%);
  -webkit-mask-image: radial-gradient(ellipse 88% 78% at 50% 32%, #000 12%, transparent 72%);
}

.hero__layer--sheen {
  background: radial-gradient(ellipse 72% 58% at 50% 20%, rgba(255, 255, 255, 0.045) 0%, transparent 62%);
  mix-blend-mode: overlay;
  opacity: 0.68;
}

.hero__layer--grid {
  opacity: 0.038;
  background-image:
    linear-gradient(rgba(200, 230, 242, 0.26) 1px, transparent 1px),
    linear-gradient(90deg, rgba(200, 230, 242, 0.26) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 74% 58% at 50% 48%, #000 18%, transparent 74%);
  -webkit-mask-image: radial-gradient(ellipse 74% 58% at 50% 48%, #000 18%, transparent 74%);
  transform: perspective(680px) rotateX(60deg) scale(1.42);
  transform-origin: center 56%;
}

.hero__layer--vignette {
  background: radial-gradient(
    ellipse 62% 52% at 50% 46%,
    transparent 0%,
    transparent 38%,
    rgba(0, 0, 0, 0.44) 72%,
    rgba(0, 0, 0, 0.84) 100%
  );
}

.hero__layer--grain {
  opacity: 0.028;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.hero__content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: min(96vw, 56rem);
  animation: heroEnter 1.1s ease-out both;
}

.hero-title {
  margin: 0;
  padding: 0;
  font-family: "Montserrat", "Futura", "Helvetica Neue", sans-serif;
  font-weight: 200;
  font-size: clamp(1.05rem, 2.75vw + 0.58rem, 1.62rem);
  line-height: 1.52;
  text-transform: uppercase;
  letter-spacing: clamp(0.28em, 2.5vw, 0.66em);
  color: #ffffff;
  text-shadow: 0 0 48px rgba(0, 0, 0, 0.48), 0 2px 22px rgba(0, 0, 0, 0.5);
}

.hero-title__line {
  display: block;
  margin-right: clamp(-0.28em, -2.5vw, -0.66em);
}

.hero-title__line + .hero-title__line {
  margin-top: clamp(0.35rem, 1.2vw, 0.65rem);
}

.hero-gloss {
  margin: clamp(1.35rem, 4vh, 2.25rem) 0 0;
  padding: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: clamp(0.78rem, 1.15vw + 0.58rem, 0.9rem);
  font-weight: 400;
  letter-spacing: 0.04em;
  line-height: 1.45;
  color: rgba(196, 212, 223, 0.52);
}

@keyframes heroEnter {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes ribbonShiftA {
  0%,
  100% {
    transform: rotate(-2.2deg) translateX(-4%) translateY(0);
  }
  50% {
    transform: rotate(-1.5deg) translateX(7%) translateY(-10px);
  }
}

@keyframes ribbonShiftB {
  0%,
  100% {
    transform: rotate(-2.2deg) translateX(3%) translateY(0);
  }
  50% {
    transform: rotate(-2.8deg) translateX(-8%) translateY(8px);
  }
}

@keyframes ribbonShiftC {
  0%,
  100% {
    transform: rotate(-2deg) translateX(-6%) translateY(0);
  }
  50% {
    transform: rotate(-2.4deg) translateX(5%) translateY(-6px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .hero__content {
    animation: none;
  }

  .hero__ribbon {
    animation: none !important;
  }
}

@media (max-width: 480px) {
  .hero-title {
    letter-spacing: clamp(0.18em, 1.6vw, 0.34em);
    font-size: clamp(0.98rem, 2.4vw + 0.72rem, 1.28rem);
  }

  .hero-title__line {
    margin-right: clamp(-0.18em, -1.6vw, -0.34em);
  }
}

@media (max-width: 520px) {
  .hero__layer--grid {
    opacity: 0.024;
    background-size: 44px 44px;
  }

  .hero__layer--stars {
    opacity: 0.4;
  }
}