:root {
  /* Illusion XR palette */
  --teal-accent: #00f2ff; /* bright logo line */
  --teal-soft: #4fa3a3;   /* proposal teal blocks */
  --bg-deep: #020617;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  height: 100%;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "SF Pro Text",
    "Segoe UI", sans-serif;
  color: #f9fafb;
  background: radial-gradient(circle at top, #071427 0, var(--bg-deep) 40%, #000 100%);
  overflow: hidden;
}

/* 3D background canvas */

#bg {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  z-index: -1;
}

/* Content overlay */

.hero {
  position: relative;
  height: 100vh;
  width: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center; /* vertical center */
  align-items: center; /* horizontal center */
  padding: 0;
}

.brand {
  max-width: 560px;
  backdrop-filter: blur(24px);
  background: linear-gradient(
    135deg,
    rgba(15, 23, 42, 0.9),
    rgba(8, 47, 73, 0.7)
  );
  border-radius: 1.75rem;
  border: 1px solid rgba(148, 163, 184, 0.35);
  padding: 2.4rem clamp(1.8rem, 3vw, 2.6rem);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.7);
}

.eyebrow {
  letter-spacing: 0.18em;
  font-size: 0.72rem;
  text-transform: uppercase;
  color: var(--teal-accent);
  margin-bottom: 0.9rem;
}

h1 {
  font-size: clamp(2.2rem, 4vw, 3.1rem);
  line-height: 1.05;
  margin-bottom: 1rem;
}

.subtitle {
  font-size: 0.98rem;
  line-height: 1.6;
  color: rgba(226, 244, 245, 0.88);
  max-width: 36rem;
  margin-bottom: 1.8rem;
}

.buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.7rem;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 160ms ease, box-shadow 160ms ease, border-color 160ms ease,
    background 160ms ease, color 160ms ease;
}

/* primary button with Illusion XR teal */

.btn.primary {
  background: linear-gradient(135deg, var(--teal-accent), #0ec8d4);
  color: #020617;
  box-shadow: 0 14px 40px rgba(0, 242, 255, 0.45);
}

.btn.primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 50px rgba(0, 242, 255, 0.6);
}

/* ghost button with teal outline */

.btn.ghost {
  background: rgba(15, 23, 42, 0.75);
  border-color: rgba(0, 242, 255, 0.35);
  color: #e5e7eb;
}

.btn.ghost:hover {
  background: rgba(15, 23, 42, 0.95);
  border-color: var(--teal-accent);
  transform: translateY(-2px);
}

/* Footer */

.footer {
  margin-top: 2.4rem;
  font-size: 0.75rem;
  color: #9ca3af;
}

/* Mobile */

@media (max-width: 640px) {
  .brand {
    padding: 1.8rem 1.5rem;
    border-radius: 1.4rem;
    margin: 0 1.2rem;
  }

  .footer {
    margin-top: 1.6rem;
  }
}