/* ベーススタイリング・共通ボタン・基本設定 */
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  overflow: hidden;
  font-family: 'Helvetica Neue', Arial, 'ヒラギノ角ゴ Pro W3', sans-serif;
  user-select: none;
  background-color: #05050a;
  color: #ffffff;
}

/* A-Frame キャンバスとホバースタイルの定義 */
canvas.a-canvas {
  cursor: default;
}
.a-mouse-cursor-hover {
  cursor: pointer !important;
}

/* 共通ボタン */
.btn {
  background: linear-gradient(135deg, #2b2b40, #1a1a28);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 10px 20px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
  font-weight: bold;
  transition: all 0.25s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
}
.btn:hover {
  background: linear-gradient(135deg, #3b3b55, #2a2a3a);
  border-color: #ffd700;
  color: #ffd700;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(255, 215, 0, 0.35);
}
.btn-gold {
  background: linear-gradient(135deg, #ffd700, #aa820a);
  color: #0b0b14;
  border: none;
  font-size: 16px;
  padding: 12px 28px;
}
.btn-gold:hover {
  background: linear-gradient(135deg, #ffe066, #c59b15);
  color: #000;
  box-shadow: 0 0 20px rgba(255, 215, 0, 0.6);
}
.btn-secondary {
  background: linear-gradient(135deg, #444455, #222233);
  color: #ddd;
}
.btn-sm {
  padding: 5px 12px;
  font-size: 12px;
}

/* 画面オーバーレイ基本構造 */
.screen-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 100;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: rgba(10, 10, 18, 0.90);
  backdrop-filter: blur(8px);
  padding: 20px;
  transition: opacity 0.4s ease, visibility 0.4s;
}
.hidden {
  opacity: 0 !important;
  pointer-events: none !important;
  visibility: hidden !important;
}