body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    background-color: #222;
    color: white;
    overflow: hidden;
}

#gameCanvas {
    background-color: #4a5d3a;
    display: block;
    border: 2px solid #333;
}

#gameInfo {
    position: absolute;
    top: 20px;
    left: 20px;
    font-size: 20px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.8);
}

#gameInfo div {
    margin-bottom: 10px;
}

.health-bar {
    display: inline-block;
    width: 150px;
    height: 20px;
    background-color: #333;
    border: 2px solid #fff;
    margin-left: 10px;
    vertical-align: middle;
}

.health-fill {
    height: 100%;
    background-color: #4f4;
    transition: width 0.3s;
}

#gameOver {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: rgba(0, 0, 0, 0.9);
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    display: none;
}

#gameOver h2 {
    margin-top: 0;
    font-size: 36px;
    color: #f44;
}

#gameOver button {
    padding: 10px 30px;
    font-size: 18px;
    background-color: #4a4;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin-top: 20px;
}

#gameOver button:hover {
    background-color: #5b5;
}

#instructions {
    position: absolute;
    bottom: 20px;
    left: 20px;
    font-size: 14px;
    opacity: 0.8;
}

.wave-message {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 48px;
    font-weight: bold;
    color: #ff0;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.8);
    display: none;
    z-index: 100;
}

.bonus {
    background-color: #44f !important;
    animation: pulse 0.5s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

.fast {
    background-color: #ff4 !important;
    animation: move 2s linear infinite;
}

@keyframes move {
    0% { transform: translateX(0); }
    50% { transform: translateX(100px); }
    100% { transform: translateX(0); }
}