:root{
  --bg:#0b1221;
  --panel:#0f1724;
  --accent:#00d1ff;
  --muted:#9aa7b2;
  --text:#e6f3ff;
}

*{box-sizing:border-box}
html,body{height:100%;margin:0;font-family:Inter,ui-sans-serif,system-ui,Segoe UI,Roboto,"Helvetica Neue",Arial}
body{
  display:flex;
  align-items:center;
  justify-content:center;
  background:linear-gradient(180deg, #071025 0%, #081426 100%);
  color:var(--text);
  padding:20px;
}

.container{
  width:880px;
  max-width:95%;
  text-align:center;
}

h1{margin:0 0 12px;font-weight:600;color:var(--accent)}

canvas{
  display:block;
  margin:0 auto;
  background:linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.01));
  border:2px solid rgba(255,255,255,0.04);
  box-shadow:0 8px 30px rgba(2,6,23,0.6);
  border-radius:6px;
}

.hint{
  color:var(--muted);
  margin:10px 0 0;
  font-size:14px;
}


/* ゲーム画面を囲むラッパー */
.game-wrapper {
  position: relative;
  display: inline-block;
  margin: 0 auto;
}

/* サウンドボタンの基本デザイン */
.sound-btn {
  position: absolute;
  right: 20px;
  bottom: 20px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: rgba(15, 23, 36, 0.8);
  border: 2px solid var(--accent);
  color: white;
  font-size: 24px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
  overflow: hidden;
  outline: none;
}

.sound-btn:hover {
  background: var(--accent);
  transform: scale(1.1);
}

/* ミュート状態の斜線エフェクト */
.sound-btn.muted .slash {
  position: absolute;
  width: 100%;
  height: 3px;
  background: #ff4757;
  transform: rotate(45deg);
  box-shadow: 0 0 5px rgba(0,0,0,0.5);
}

.sound-btn.muted {
  border-color: #ff4757;
  opacity: 0.7;
}

/* 音声ステータス表示 */
#voice-status {
  position: absolute;
  left: 20px;
  bottom: 20px;
  color: var(--accent);
  font-size: 14px;
  font-family: monospace;
  pointer-events: none;
  text-shadow: 0 0 5px rgba(0,0,0,0.5);
}