body, html {
    margin: 0;
    padding: 0;
    overflow: hidden;
}

#toolbar {
    position: fixed;
    top: 10px;
    left: 10px;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.8);
    padding: 10px;
    border-radius: 5px;
}

.tool-btn {
    margin: 2px;
    padding: 5px 10px;
    cursor: pointer;
}

.tool-btn.active {
    background-color: #007bff;
    color: white;
}

#canvas {
    position: absolute;
    top: 0;
    left: 0;
}