/* 正交引线 SVG 层 */
.app-leader-svg {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 540px;
  height: 640px;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 3;
}
.leader-group {
  opacity: 0;
  transition: opacity 0.2s ease-out;
}
.leader-group.is-drawn {
  opacity: 1;
}
.leader-dot {
  fill: var(--ink, #1C1917);
  transition: fill 0.3s ease;
}
.leader-line {
  fill: none;
  stroke: rgba(28, 25, 23, 0.42);
  stroke-width: 1.2;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-dasharray: 240;
  stroke-dashoffset: 240;
  transition: stroke-dashoffset 380ms cubic-bezier(0.33, 1, 0.68, 1), stroke 0.3s ease, stroke-width 0.3s ease;
}
.leader-group.is-drawn .leader-line {
  stroke-dashoffset: 0;
}
.leader-group.is-lit .leader-dot {
  fill: var(--coral, #F46B45);
}
.leader-group.is-lit .leader-line {
  stroke: var(--coral, #F46B45);
  stroke-width: 1.8;
}

/* 注释卡样式强化与错峰入场 */
.part-callout {
  position: absolute;
  z-index: 3;
  max-width: 185px;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(8px);
  border: 1px solid #F0DFD5;
  border-radius: 10px;
  padding: 9px 12px;
  box-shadow: 0 8px 25px rgba(89, 54, 42, 0.08);
  line-height: 1.3;
}
.device-art.onboarding-stage .part-callout {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 420ms ease-out, transform 420ms cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s ease, border-color 0.25s ease;
  cursor: pointer;
}
.device-art.onboarding-stage .part-callout.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.device-art.onboarding-stage .part-callout:hover,
.device-art.onboarding-stage .part-callout.is-hovered {
  border-color: var(--coral, #F46B45);
  box-shadow: 0 10px 30px rgba(244, 107, 69, 0.2);
  transform: translateY(-2px);
}
.device-art.onboarding-stage .part-callout::before,
.device-art.onboarding-stage .part-callout::after {
  display: none; /* 由正交折线 app-leader-svg 接管 */
}

/* 5 张注释卡的具体绝对定位 (与 540x640 引线完美对位) */
.device-art.onboarding-stage .part-callout.c-mouthpiece { top: 48px; left: 0; }
.device-art.onboarding-stage .part-callout.c-dial { top: 175px; right: 0; }
.device-art.onboarding-stage .part-callout.c-sensor { top: 226px; left: 0; }
.device-art.onboarding-stage .part-callout.c-ring { top: 297px; right: 0; }
.device-art.onboarding-stage .part-callout.c-body { top: 483px; left: 0; }

.part-callout .part-num {
  display: block;
  font-size: 9px;
  font-weight: 850;
  letter-spacing: .12em;
  color: var(--deep);
  margin-bottom: 2px;
}
.part-callout strong {
  display: block;
  font-size: 13px;
  font-weight: 800;
  color: var(--ink);
  line-height: 1.25;
}
.part-callout small {
  display: block;
  font-size: 11px;
  color: var(--muted);
  line-height: 1.35;
  margin-top: 2px;
}

/* 底部标语与重播按钮 */
.device-art.onboarding-stage .device-caption {
  position: absolute;
  left: 14px;
  bottom: 14px;
  font-size: 9px;
  color: #9B887E;
  letter-spacing: .12em;
  font-weight: 800;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.6s ease-out 0.4s;
}
.device-art.onboarding-stage.is-annotated .device-caption {
  opacity: 1;
}

.device-replay-btn {
  position: absolute;
  right: 14px;
  bottom: 12px;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(28, 25, 23, 0.12);
  border-radius: 999px;
  padding: 5px 12px;
  font-size: 11px;
  font-weight: 700;
  color: var(--ink, #1C1917);
  cursor: pointer;
  z-index: 10;
  opacity: 0;
  pointer-events: none;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.05);
  transition: opacity 0.4s ease, background 0.2s ease, transform 0.2s ease, color 0.2s ease;
}
.device-art.onboarding-stage.is-annotated .device-replay-btn {
  opacity: 1;
  pointer-events: auto;
}
.device-replay-btn:hover {
  background: #FFF;
  color: var(--deep, #B6422A);
  border-color: var(--coral, #F46B45);
  transform: scale(1.04);
}
.device-replay-btn svg {
  transition: transform 0.5s ease;
}
.device-replay-btn:hover svg {
  transform: rotate(180deg);
}

.device-bullets div {
  align-items: baseline;
}
.device-bullets em {
  font-style: normal;
  color: var(--muted);
  font-size: 12px;
  margin-left: 6px;
}