:root {
  --bg-top: #e0f4ff;
  --bg-bottom: #9fd8f5;
  --text: #0b3954;
  --muted: #3f6e8a;
  --card: rgba(255, 255, 255, 0.6);
  --wave: rgba(30, 136, 199, 0.25);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-top: #061a2b;
    --bg-bottom: #0b3954;
    --text: #e6f6ff;
    --muted: #8fbad3;
    --card: rgba(255, 255, 255, 0.06);
    --wave: rgba(87, 190, 255, 0.15);
  }
}

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

html, body { height: 100%; }

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, var(--bg-top), var(--bg-bottom));
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 16px;
  overflow: hidden;
  position: relative;
}

.card {
  position: relative;
  z-index: 2;
  max-width: 520px;
  width: 100%;
  text-align: center;
  padding: 48px 32px;
  border-radius: 24px;
  background: var(--card);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: 0 10px 40px rgba(11, 57, 84, 0.15);
}

.dolphin {
  font-size: 72px;
  line-height: 1;
  margin-bottom: 16px;
  animation: jump 3s ease-in-out infinite;
  display: inline-block;
}

h1 {
  font-size: clamp(1.6rem, 5vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.lead {
  font-size: 1.1rem;
  line-height: 1.5;
  margin-bottom: 8px;
}

.muted { color: var(--muted); }

.btn {
  display: inline-block;
  margin-top: 24px;
  padding: 12px 24px;
  border-radius: 999px;
  background: #1e88c7;
  color: #fff;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(30, 136, 199, 0.35);
  transition: transform 0.15s, background 0.15s;
}
.btn:hover { background: #166fa3; transform: translateY(-2px); }
.btn:focus-visible { outline: 3px solid var(--text); outline-offset: 3px; }

.list {
  text-align: left;
  margin: 16px auto 0;
  max-width: 380px;
  line-height: 1.7;
  list-style: none;
}

footer {
  position: absolute;
  bottom: 16px;
  z-index: 2;
  font-size: 0.85rem;
  color: var(--muted);
}

.waves {
  position: absolute;
  inset: auto 0 0 0;
  height: 200px;
  z-index: 1;
  pointer-events: none;
}

.wave {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 200%;
  height: 100%;
  background: radial-gradient(circle at 50% 100%, var(--wave) 40%, transparent 41%) 0 0 / 200px 120px repeat-x;
  animation: drift 12s linear infinite;
}
.w2 { bottom: -20px; opacity: 0.7; animation-duration: 18s; animation-direction: reverse; }
.w3 { bottom: -40px; opacity: 0.5; animation-duration: 24s; }

@keyframes jump {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-14px) rotate(-8deg); }
}

@keyframes drift {
  from { transform: translateX(0); }
  to { transform: translateX(-200px); }
}

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