body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #111;
    color: white;
}

#loadingScreen {
    background: black;
    color: white;
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    text-align: center;
}

#loadingScreen img#logo {
    width: 150px;
    margin-bottom: 10px;
}

#loadingScreen h1 {
    font-size: 20px;
    margin: 10px 0;
}

#loadingScreen button {
    background: #222;
    color: white;
    border: 1px solid white;
    padding: 5px 10px;
    cursor: pointer;
}

#gameScreen {
    display: none;
    flex-direction: row;
}

#leftPanel {
    width: 200px;
    padding: 10px;
    background: #222;
}

#centerArea {
    flex: 1;
    text-align: center;
}

#clickButton {
    width: 150px;
    height: 150px;
    font-size: 30px;
    background: #333;
    border: 2px solid white;
    cursor: pointer;
}

#bottomBar {
    margin-top: 20px;
    background: #000;
    padding: 10px;
    text-align: center;
}

.upgrade {
    background: #333;
    margin: 5px 0;
    padding: 5px;
    cursor: pointer;
    border: 1px solid #555;
}

.upgrade:hover {
    background: #444;
}