body {
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: linear-gradient(135deg, #1a2a6c, #b21f1f, #fdbb2d);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #fff;
    overflow: hidden;
}

.game-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
}

canvas {
    background: linear-gradient(to right, #141e30, #243b55);
    border: 3px solid #fff;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5), 0 0 30px rgba(255, 255, 255, 0.2);
    margin-bottom: 20px;
}

.game-info {
    margin-top: 10px;
    display: flex;
    justify-content: space-between;
    width: 800px;
    font-size: 20px;
    font-weight: 600;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    background: rgba(0, 0, 0, 0.5);
    padding: 15px 25px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

#playerScore {
    color: #4fc3f7;
    padding: 8px 15px;
    border-radius: 5px;
    background: rgba(0, 0, 0, 0.3);
}

#cpuScore {
    color: #ff8a65;
    padding: 8px 15px;
    border-radius: 5px;
    background: rgba(0, 0, 0, 0.3);
}

#restartButton {
    padding: 10px 25px;
    background: linear-gradient(to right, #ff416c, #ff4b2b);
    color: white;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-size: 18px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(255, 75, 43, 0.4);
}

#restartButton:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(255, 75, 43, 0.6);
}

#restartButton:active {
    transform: translateY(1px);
}

/* ゲームタイトル */
.game-title {
    position: absolute;
    top: -80px;
    font-size: 36px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: #fff;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.7), 0 0 20px rgba(255, 255, 255, 0.5);
    margin-bottom: 20px;
}

/* 装飾的な要素 */
.decoration {
    position: absolute;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

.decoration::before, .decoration::after {
    content: '';
    position: absolute;
    width: 200px;
    height: 200px;
    border-radius: 50%;
    opacity: 0.1;
}

.decoration::before {
    background: radial-gradient(circle, #ff4b2b, transparent);
    top: -100px;
    left: -100px;
}

.decoration::after {
    background: radial-gradient(circle, #4fc3f7, transparent);
    bottom: -100px;
    right: -100px;
}