body, html {
  overscroll-behavior: none;
  touch-action: none;
  margin: 0;
  padding: 0;
}

/* グローバルに適用して全要素の文字選択を禁止 */
* {
  -webkit-user-select: none;  /* Chrome, Safari, 新しい Edge など */
  -moz-user-select:    none;  /* Firefox */
  -ms-user-select:     none;  /* 古い IE/Edge */
  user-select:         none;  /* 標準仕様 */
}

/* — 変更後 — */
.canvas-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  display: flex;
  justify-content: center;    /* 横方向は中央 */
  align-items: flex-start;    /* 縦方向は上寄せ */
  background: black;          /* キャンバスの背景と合わせる */
  overflow: visible;          /* メニュー等のオーバーフローも許可 */
}
#gameCanvas {
  transform-origin: top center;
}

canvas {
  display: block;
  background-color: black;
  image-rendering: pixelated;
  z-index: 0;             /* ← 追加！ */
  position: relative;     /* ← 必要！(z-index効かせるため) */
}

#canvas-container {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  background: black;
  overflow: visible; /* メニューの見切れ防止 */
}

/* --- Upgrade Menu --- */
#upgrade-menu,
.upgrade-menu {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(150%, -50%);
  transition: transform 0.5s ease-out;
  display: none;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2vw;
  padding: 1vh;
  max-width: 100vw;
  z-index: 1000;
  pointer-events: auto;
}

/* 表示時：中央にスライドイン */
#upgrade-menu.open,
.upgrade-menu.open {
  display: flex;
  transform: translate(-50%, -50%);
}

/* 各アイテム（レスポンシブ対応） */
#upgrade-menu .upg-item,
.upgrade-menu .upg-item {
  width: clamp(50px, 9vw, 100px);
  height: clamp(50px, 9vw, 100px);
  flex-shrink: 0;
  padding: 0;
  margin: 0;
}
@media (min-width: 800px) {
  #upgrade-menu .upg-item,
  .upgrade-menu .upg-item {
    width: clamp(80px, 20vw, 20px);
    height: clamp(80px, 15vw, 200px);
  }
}
@media (min-width: 1000px) {
  #upgrade-menu .upg-item,
  .upgrade-menu .upg-item {
    width: clamp(150px, 20vw, 200px);
    height: clamp(150px, 20vw, 200px);
  }
}

/* アイコン */
#upgrade-menu .upgrade-icon,
.upgrade-menu .upgrade-icon {
  width: 100%;
  height: 100%;
}

#upgrade-menu .upg-item .label,
.upgrade-menu .upg-item .label {
  font-size: 10px;
  color: white;
  text-align: center;
  margin-top: 4px;
  white-space: nowrap;
}
@media (min-width: 800px) {
  #upgrade-menu .upg-item .label,
 .upgrade-menu .upg-item .label {
  font-size: 20px;
  color: white;
  text-align: center;
  margin-top: 4px;
  white-space: nowrap;
}
}
@media (min-width: 1000px) {
  #upgrade-menu .upg-item .label,
 .upgrade-menu .upg-item .label {
  font-size: 30px;
  color: white;
  text-align: center;
  margin-top: 4px;
  white-space: nowrap;
}
}

#upgrade-menu .upg-item img,
.upgrade-menu .upg-item img {
  width: 100%;
  height: auto;
}

#upgrade-menu .upg-item,
.upgrade-menu .upg-item,
#upgrade-menu .upg-item.hover,
.upgrade-menu .upg-item.hover,
#upgrade-menu .upg-item:hover,
.upgrade-menu .upg-item:hover {
  transition: transform 0.1s;
}
#upgrade-menu .upg-item.hover,
.upgrade-menu .upg-item.hover,
#upgrade-menu .upg-item:hover,
.upgrade-menu .upg-item:hover {
  transform: scale(1.1);
}