body {
    margin: 0;
    padding: 0;
    background: #2c3e50;
    font-family: 'Courier New', monospace;
    overflow: hidden;
}

#gameCanvas {
    border: 2px solid #34495e;
    background: #ecf0f1;
    display: block;
    margin: 0 auto;
}

#ui {
    position: absolute;
    top: 10px;
    left: 10px;
    color: white;
    font-size: 14px;
    z-index: 10;
}

#shopButton {
    position: absolute;
    bottom: 20px;
    left: 20px;
    padding: 10px 20px;
    background: #e74c3c;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
}

#shopButton:hover {
    background: #c0392b;
}

#shopModal {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: #34495e;
    border: 3px solid #2c3e50;
    border-radius: 10px;
    padding: 20px;
    color: white;
    display: none;
    z-index: 20;
    max-width: 600px;
}

.tower-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 10px 0;
    padding: 10px;
    background: #2c3e50;
    border-radius: 5px;
    cursor: pointer;
}

.tower-item:hover {
    background: #34495e;
}

.tower-item.disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

#closeShop {
    position: absolute;
    top: 10px;
    right: 15px;
    background: none;
    border: none;
    color: white;
    font-size: 20px;
    cursor: pointer;
}

#gameOverModal {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: #e74c3c;
    border: 3px solid #c0392b;
    border-radius: 10px;
    padding: 30px;
    color: white;
    display: none;
    z-index: 30;
    text-align: center;
}

#restartButton {
    padding: 15px 30px;
    background: #2c3e50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 18px;
    margin-top: 20px;
}

#repairButton {
    position: absolute;
    bottom: 20px;
    right: 20px;
    padding: 10px 20px;
    background: #27ae60;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
}

#repairButton:hover {
    background: #2ecc71;
}

#repairButton:disabled {
    background: #7f8c8d;
    cursor: not-allowed;
}

#demolishButton {
    position: absolute;
    bottom: 20px;
    right: 180px;
    /* repairButton left side */
    padding: 10px 20px;
    background: #c0392b;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    font-weight: bold;
}

#demolishButton:hover {
    background: #e74c3c;
}

#demolishButton:disabled {
    background: #7f8c8d;
    cursor: not-allowed;
}