/* 画像・図面・動画のクリック拡大(サイズ統一枠つき) */
.lb-overlay {
  position: fixed; inset: 0; z-index: 1000;
  background: rgba(20, 20, 20, .8);
  display: flex; align-items: center; justify-content: center;
}
.lb-frame {
  width: min(860px, 92vw); height: min(620px, 80vh);
  background: #fff; border-radius: 6px; padding: 16px 16px 44px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, .45);
  position: relative; display: flex; align-items: center; justify-content: center;
}
.lb-frame img, .lb-frame video, .lb-frame iframe {
  max-width: 100%; max-height: 100%; object-fit: contain;
}
.lb-frame iframe { width: 100%; height: 100%; border: 0; }
.lb-caption {
  position: absolute; left: 16px; right: 16px; bottom: 10px;
  text-align: center; font-size: 15px; color: #343a40;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.lb-close {
  position: absolute; top: -14px; right: -14px; width: 36px; height: 36px;
  border-radius: 50%; background: #800000; color: #fff; border: 2px solid #fff;
  font-size: 18px; line-height: 1; cursor: pointer;
}
.lb-prev, .lb-next {
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(255, 255, 255, .9); border: 1px solid #ccc;
  font-size: 20px; cursor: pointer;
}
.lb-prev { left: -56px; }
.lb-next { right: -56px; }
@media (max-width: 767px) {
  .lb-prev { left: 6px; }
  .lb-next { right: 6px; }
}