:root {
  --phosphor: #38eb6b;
  --peak: #8cffb3;
  --screen: #050a07;
  --grid: rgba(33, 92, 46, 0.55);
  --text: #f5f5f7;
  --dim: rgba(245, 245, 247, 0.6);
}
* { box-sizing: border-box; margin: 0; }
html, body { height: 100%; background: #000; color: var(--text); }
body {
  font: 17px/1.4 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100%;
  padding: 24px 16px;
}
main { width: min(520px, 100%); }

/* The breath scope: a phosphor screen with its graticule, the wave scrolling at
   about six breaths a minute. */
.scope {
  position: relative;
  aspect-ratio: 5 / 2;
  border-radius: 18px;
  overflow: hidden;
  background:
    linear-gradient(var(--grid) 1px, transparent 1px) 0 0 / 100% 25%,
    linear-gradient(90deg, var(--grid) 1px, transparent 1px) 0 0 / 12.5% 100%,
    var(--screen);
  border: 1px solid rgba(71, 204, 102, 0.45);
  box-shadow: 0 0 40px rgba(56, 235, 107, 0.12);
  margin-bottom: 36px;
}
.scope svg { position: absolute; inset: 12% 0; width: 100%; height: 76%; }
.scope path {
  fill: none;
  stroke: var(--phosphor);
  stroke-width: 3;
  vector-effect: non-scaling-stroke;
  filter: drop-shadow(0 0 4px rgba(56, 235, 107, 0.9)) drop-shadow(0 0 12px rgba(56, 235, 107, 0.45));
}
.wave { animation: scroll 11s linear infinite; }
@keyframes scroll { to { transform: translateX(-200px); } }
.label {
  position: absolute; left: 16px; bottom: 12px;
  font: 700 11px/1 ui-monospace, "SF Mono", Menlo, monospace;
  letter-spacing: 2px; color: rgba(56, 235, 107, 0.45);
}
.lamp {
  position: absolute; right: 16px; bottom: 12px;
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--peak); box-shadow: 0 0 8px var(--peak);
  animation: lamp 11s ease-in-out infinite;
}
@keyframes lamp { 0%, 100% { opacity: 0.25; } 50% { opacity: 1; } }

h1 { font-size: 44px; font-weight: 700; letter-spacing: -0.8px; line-height: 1.05; }
p { margin-top: 10px; font-size: 19px; color: var(--dim); }
p.soon { margin-top: 28px; font-size: 13px; font-weight: 600; letter-spacing: 0.6px; text-transform: uppercase; color: rgba(245, 245, 247, 0.45); }

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