* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: #000;
}

#camerafeed {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

/* ─── スキャンガイド ─────────────────────────────── */
#scan-overlay {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  pointer-events: none;
  transition: opacity 0.35s ease;
}

#scan-overlay.hidden {
  opacity: 0;
}

.scan-frame {
  position: relative;
  width: min(72vw, 420px);
  border-radius: 10px;
  overflow: hidden;
  box-shadow:
    0 0 0 2px rgba(77, 232, 224, 0.8),
    0 0 24px rgba(77, 232, 224, 0.35);
}

.scan-frame img {
  display: block;
  width: 100%;
  opacity: 0.45;
}

.scan-line {
  position: absolute;
  left: 0;
  right: 0;
  top: 2%;
  height: 3px;
  background: linear-gradient(90deg, transparent, #4de8e0, transparent);
  animation: scan-sweep 2.4s ease-in-out infinite;
}

@keyframes scan-sweep {
  0% { top: 2%; }
  50% { top: 95%; }
  100% { top: 2%; }
}

.scan-text {
  margin: 0;
  color: #fff;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 15px;
  letter-spacing: 0.12em;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.6);
  animation: scan-pulse 2s ease-in-out infinite;
}

@keyframes scan-pulse {
  0%, 100% { opacity: 0.65; }
  50% { opacity: 1; }
}