html, body {
  margin: 0;
  padding: 0;
  background: #050512;
  color: white;
  font-family: "Malgun Gothic", "Apple SD Gothic Neo", system-ui, sans-serif;
  height: 100%;
  overflow: hidden;
}

#app {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  background: radial-gradient(circle at 50% 50%, #17113a, #020208 72%);
}

canvas {
  width: min(100vw, calc(100vh * 16 / 9));
  height: min(100vh, calc(100vw * 9 / 16));
  display: block;
  background: #080818;
}

.signal {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  background: rgba(0,0,0,.66);
  z-index: 10;
}

.hidden { display: none; }

.signalBox {
  width: min(960px, 92vw);
  max-height: 86vh;
  overflow: auto;
  background: rgba(10,10,24,.95);
  border: 2px solid rgba(255,255,255,.75);
  border-radius: 28px;
  box-shadow: 0 0 36px rgba(167,90,255,.55);
  padding: 28px;
}

h2 {
  margin: 0 0 16px 0;
  text-align: center;
  letter-spacing: -0.04em;
  font-size: 34px;
}

p { line-height: 1.55; }
.muted { color: #d8d8e8; }

.row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

button {
  border: 2px solid rgba(255,255,255,.75);
  background: linear-gradient(180deg, #6939ff, #28146d);
  color: white;
  border-radius: 16px;
  font-weight: 800;
  font-size: 18px;
  padding: 12px 18px;
  cursor: pointer;
  box-shadow: 0 0 18px rgba(180,110,255,.35);
}

button:hover {
  transform: translateY(-1px);
  filter: brightness(1.15);
}

textarea, input {
  box-sizing: border-box;
  width: 100%;
  background: #080812;
  color: #fff;
  border: 1px solid #8f7bff;
  border-radius: 12px;
  padding: 12px;
  font-family: ui-monospace, Consolas, monospace;
  font-size: 13px;
}

textarea {
  min-height: 120px;
  resize: vertical;
}

.steps {
  display: grid;
  gap: 14px;
  margin-top: 20px;
}

.copy { background: linear-gradient(180deg, #ff7fc9, #7a1767); }
.ok { color: #fff6a8; font-weight: 800; }
.warn { color: #ffcc9b; font-weight: 800; }