.portfolio {
    text-align: center;
    padding: 50px;
}

.portfolio h2 {
    font-size: 2.5em;
    color: #007bff;
    margin-bottom: 30px;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(300px, 1fr));
    gap: 20px;
}

.portfolio-item {
    position: relative;
    overflow: hidden;
}

.portfolio-item img {
    width: 100%;
    height: 340px;
    display: block;
}

.overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(0, 0, 0, 0.7);
    color: #fff;
    padding: 20px;
    text-align: center;
    opacity: 0;
    transition: opacity 0.3s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100%;
}

.portfolio-item:hover .overlay {
    opacity: 1;
}

.overlay .text {
    font-size: 1.2em;
    padding: 0 10px;
}

/* Media queries for responsiveness */
@media (max-width: 1200px) {
    .portfolio-grid {
        grid-template-columns: repeat(3, minmax(300px, 1fr));
    }
}

@media (max-width: 992px) {
    .portfolio-grid {
        grid-template-columns: repeat(2, minmax(300px, 1fr));
    }

    .portfolio h2 {
        font-size: 2em;
    }
}

@media (max-width: 768px) {
    .portfolio-grid {
        grid-template-columns: 1fr;
    }

    .portfolio h2 {
        font-size: 1.75em;
    }
}

@media (max-width: 576px) {
    .portfolio {
        padding: 20px;
    }

    .portfolio h2 {
        font-size: 1.5em;
    }

    .overlay {
        padding: 10px;
    }

    .overlay .text {
        font-size: 1em;
    }
}