:root {
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background:
    radial-gradient(circle at 50% 12%, rgb(130 229 255 / 35%), rgb(130 229 255 / 0%) 36%),
    linear-gradient(180deg, #3d9db6 0%, #1f5f8b 35%, #153a64 62%, #0c1d3b 100%);
  color: #eaf8ff;
  overflow: hidden;
}

#starfield {
  position: fixed;
  inset: 0;
}

#starfield::after {
  content: "";
}

.hero {
  position: relative;
  z-index: 2;
  min-height: 100vh;
  display: grid;
  place-content: center;
  text-align: center;
  gap: 1rem;
  padding: 1.5rem;
  background: linear-gradient(180deg, rgb(6 39 60 / 30%), rgb(4 18 38 / 58%));
}

.badge {
  justify-self: center;
  margin: 0;
  padding: 0.35rem 0.9rem;
  border: 1px solid #7fdcff;
  border-radius: 999px;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #d9f6ff;
  background-color: rgb(80 194 232 / 20%);
  box-shadow: 0 0 16px rgb(80 194 232 / 42%);
}

h1 {
  margin: 0;
  font-size: clamp(2.3rem, 7vw, 5rem);
  line-height: 1.05;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #d8f6ff;
  text-shadow: 0 0 8px #7fdcff, 0 0 28px #48a8d8, 0 0 45px #1f4c8c;
  animation: shimmer 5s ease-in-out infinite;
}

.subtitle {
  margin: 0;
  font-size: clamp(1rem, 2.5vw, 1.35rem);
  color: #caecff;
}

#pulseButton {
  justify-self: center;
  margin-top: 0.4rem;
  border: none;
  border-radius: 999px;
  padding: 0.85rem 1.4rem;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #052741;
  background: linear-gradient(130deg, #9be8ff, #58c3e7 55%, #63d4ff);
  cursor: pointer;
  box-shadow: 0 0 30px rgb(88 195 231 / 58%);
  transition: transform 120ms ease, box-shadow 120ms ease;
}

#pulseButton:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 0 46px rgb(127 220 255 / 72%);
}

#pulseButton:active {
  transform: scale(0.98);
}

.hint {
  margin-top: 0.2rem;
  color: #c8ebff;
}

.hint code {
  color: #9be8ff;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    repeating-linear-gradient(
      0deg,
      rgb(30 93 149 / 0%),
      rgb(30 93 149 / 0%) 34px,
      rgb(130 229 255 / 14%) 35px
    );
  opacity: 0.22;
  pointer-events: none;
}

@keyframes shimmer {
  0%,
  100% {
    filter: hue-rotate(0deg);
  }
  50% {
    filter: hue-rotate(35deg);
  }
}