body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #222;
    color: #fff; /* Text color set to white */
    flex-direction: column;
}

#quiz {
    text-align: center;
    margin-top: 20px; /* Added margin for spacing */
}

#keyboard {
    display: flex;
    margin-top: 20px;
}

.white-key, .black-key {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    font-size: 20px;
    font-weight: bold;
}

.white-key {
    width: 40px;
    height: 200px;
    background-color: #f0f0f0; /* Light gray for white keys */
    border: 2px solid #333; /* Darker border for contrast */
    color: #333; /* Darker border for contrast */
    margin: 0 2px;
}

.black-key {
    width: 30px;
    height: 120px;
    background-color: #333; /* Dark background for black keys */
    position: absolute;
    margin: 0 1px;
    left: 30px;
    z-index: 1;
    color: white;
    border: 2px solid #333; /* Darker border for contrast */
}

.selected {
    background-color: #4CAF50 !important; /* Green for selected keys */
    color: white !important;
    border: 2px solid #333 !important; /* Darker border for contrast */
}

.pending {
    outline: 3px solid yellow !important; /* Yellow outline for pending selection */
}

.white-key .number {
    position: absolute;
    bottom: 10px;
    pointer-events: none;
}

.black-key .number {
    position: absolute;
    top: 10px;
    pointer-events: none;
}

.flash-red {
    background-color: #FF5252 !important; /* Red for flash animation */
    border: 2px solid #333 !important; /* Darker border for contrast */
}

.flash-yellow {
    background-color: #FFEB3B !important; /* Yellow for flash animation */
    border: 2px solid #333 !important; /* Darker border for contrast */
}