.container {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin: 10px;
}

.column {
    flex: 1;
    max-width: 200px;
    padding: 15px;
    background-color: #f8f9fa;
    border-radius: 8px;
    border: 2px solid #ddd;
}

.item {
    padding: 10px;
    margin: 10px 0;
    background: white;
    border: 1px solid #ccc;
    cursor: pointer;
    border-radius: 4px;
    transition: 0.3s;
}

.item:hover {
    background-color: #e9ecef;
}

/* Trạng thái khi click */
.selected {
    background-color: #007bff !important;
    color: white;
    border-color: #0056b3;
}

.matched {
    background-color: #28a745 !important;
    color: white;
    visibility: hidden;
}

/* Ẩn đi khi đúng */
.wrong {
    background-color: #dc3545 !important;
    color: white;
}

button#home-btn {
    margin-top: 30px;
    padding: 10px 20px;
    cursor: pointer;
}