/* ===== Flip card container ===== */
/* 关键：轴心在中心 + 3D 视距在中心；宽度按场景切换 */
.flip-container {
  position: absolute;
  top: 60px;
  left: calc(50% - (var(--card-width-lg) / 2));
  width: var(--card-width-lg);
  perspective: 1000px;
  perspective-origin: 50% 50%;
  z-index: 10;
}
.flip-container.show-research {
  width: var(--card-width-research);
  /* 注意：left/top 会被 JS 改写以保持中心不动 */
}

.flip-container.show-blog {
  width: var(--card-width-blog);
}

.flipper {
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.6s;
  transform-origin: 50% 50%;
}

.flip-container.flipped .flipper { transform: rotateY(180deg); }

/* 三个面严格中心旋转 */
.front, .back {
  position: absolute;
  width: 100%;
  border-radius: 20px;
  box-shadow: var(--shadow);
  backface-visibility: hidden;
  background: white;
  transform-origin: 50% 50%;
}
.front { z-index: 0; }
.back  { transform: rotateY(180deg); box-sizing: border-box; }

/* 哪个背面显示 */
.back { display: none; }
.flip-container.show-poem .back-poem { display: block; }
.flip-container.show-research .back-research { display: block; }
.flip-container.show-blog .back-blog { display: block; }

/* Front content wrapper (draggable handle) */
#block-wrapper {
  width: 100%;
  background: white;
  border-radius: 20px;
  box-shadow: var(--shadow);
  cursor: grab;
  z-index: 0;
}

#block-wrapper img {
  user-drag: none;
  -webkit-user-drag: none;
  pointer-events: auto;
}

#text { width: 100%; margin: 0 auto; text-align: left; font-size: 18px; }
#text #cat { text-align: center; margin: 0 auto; }

#cat-wrap {
  position: relative;
  display: block;
}
#cat-overlay {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgba(0, 0, 0, 0.55);
  color: white;
  font-size: 14px;
  line-height: 1.8;
  text-align: center;
  padding: 12px 20px;
  border-radius: 8px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.5s ease;
  white-space: nowrap;
}
#cat-overlay.visible {
  opacity: 1;
  pointer-events: auto;
}

/* Menu/Terminal */
#menu { width: 400px; margin: 0 auto; }
#terminal { margin: 0 auto; }

/* Cursor change on image hover */
#cat-pic:hover {
  cursor: url("https://kate0115.net/pic/cursor_grey.gif"), url("https://kate0115.net/pic/cursor.cur"), default;
}