.bingo-card {
    background: white;
    border: 3px solid #333;
    border-radius: 10px;
    padding: 15px;
    margin: 15px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    max-width: 300px;
}

.bingo-header {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 2px;
    margin-bottom: 5px;
}

.bingo-letter {
    background: #17a2b8;
    color: white;
    text-align: center;
    font-weight: bold;
    font-size: 24px;
    padding: 10px;
    border-radius: 5px;
}

.bingo-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 2px;
}

.bingo-cell {
    width: 50px;
    height: 50px;
    border: 2px solid #333;
    background: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    border-radius: 5px;
}

.bingo-cell:hover {
    background: #e9ecef;
    transform: scale(1.05);
}

.bingo-cell.highlighted {
    background: #ffc107;
    color: #333;
    border-color: #e0a800;
}

.bingo-cell.free-space {
    background: #28a745;
    color: white;
    font-size: 14px;
    border-color: #1e7e34;
}

.card-title {
    text-align: center;
    margin-bottom: 15px;
    color: #17a2b8;
    font-weight: bold;
}

#bingo-generator {
    padding: 20px 0;
}

@media (max-width: 768px) {
    .bingo-card {
        margin: 10px auto;
    }
}

@media (max-width: 768px) {
    .bingo-cell {
        width: 45px;
        height: 45px;
        font-size: 14px;
    }
}

@media (max-width: 768px) {
    .bingo-letter {
        font-size: 20px;
        padding: 8px;
    }
}

.card-history {
    background-color: #9fcd2d;
}

.header-bingo {
    background-color: #fef8ea;
}