.pool-container {
    width: 100%;
    max-width: 600px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    overflow: hidden; /* Crucial for containing the sliding effect */
    position: relative;
}

.choose-box-container {
    display: flex;
    gap: 20px;
    align-items: center;
}

.choose-box-container button {
    padding: 10px 20px;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    margin-top: 10px;
}

.left-box, .right-box {
    border: 2px solid #0000ff;
    padding: 10px;
    width: 200px;
}

#availableItems, #selectedItems, .myselect {
    width: 100%;
    height: 200px;
}

.controls {
    display: flex;
    flex-direction: column;
    gap: 10px;
}