#portfolio {
    background: linear-gradient(135deg, #f8f9fa, #ffffff);
    padding: 4rem 2rem;
    position: relative;
    overflow: hidden;
}

#portfolio h2 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 0.5rem;  
    font-size: 1.8rem;    
    text-transform: uppercase;
    letter-spacing: 2px;  
    font-weight: 700;
    position: relative;
    background: linear-gradient(90deg, #007bff 30%, #6c757d 100%);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
    display: inline-block;
    padding-bottom: 10px;
    line-height: 1;
    margin-left: 50%;  
    transform: translateX(-50%);
}

#portfolio h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 80px;  
    height: 3px;
    background: linear-gradient(to right, #007bff, #6c757d);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.4s ease-in-out;
}

#portfolio h2:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

.portfolio-categories {
    display: flex;
    justify-content: center;
    margin-bottom: 3rem;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.portfolio-category-btn {
    padding: 0.8rem 1.8rem;
    background: transparent;
    color: #495057;
    border: 2px solid #007bff;
    border-radius: 40px;
    cursor: pointer;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    transition: all 0.4s ease;
}

.portfolio-category-btn.active,
.portfolio-category-btn:hover {
    background: linear-gradient(135deg, #007bff, #6c757d);
    color: white;
    box-shadow: 
        0 10px 25px rgba(0, 123, 255, 0.2),
        0 6px 15px rgba(108, 117, 125, 0.15);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.portfolio-item {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 
        0 15px 35px rgba(0, 123, 255, 0.1),
        0 10px 25px rgba(0, 123, 255, 0.05);
    border: 1px solid rgba(0, 123, 255, 0.1);
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}

.portfolio-item:hover {
    transform: translateY(-10px);
    box-shadow: 
        0 20px 40px rgba(0, 123, 255, 0.15),
        0 15px 30px rgba(0, 123, 255, 0.1);
}

.portfolio-item img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    border-radius: 10px;
    transition: transform 0.4s ease;
}

.portfolio-item:hover img {
    transform: scale(1.05);
}

.portfolio-item h3 {
    color: #2c3e50;
    margin: 1rem 0;
    font-size: 1.3rem;
    letter-spacing: 1px;
    font-weight: 700;
    position: relative;
}

.portfolio-item h3::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 40px;
    height: 2px;
    background: linear-gradient(to right, #007bff, #6c757d);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.portfolio-item:hover h3::after {
    opacity: 1;
}

.portfolio-item p {
    color: #495057;
    opacity: 0.9;
    line-height: 1.6;
    margin-bottom: 1rem;
}

.app-button {
    display: inline-block;
    margin-top: 1.5rem;
    padding: 0.5rem 1.2rem;
    background: linear-gradient(135deg, #007bff, #6c757d);
    color: white;
    text-decoration: none;
    border-radius: 40px;
    font-weight: 600;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    transition: all 0.4s ease;
    box-shadow: 
        0 8px 20px rgba(0, 123, 255, 0.15),
        0 4px 10px rgba(108, 117, 125, 0.1);
    font-size: 0.7rem;
    text-align: center;
    width: 150px;
    margin-left: 50%;
    transform: translateX(-50%);
}

.app-button:hover {
    transform: translateY(-5px) translateX(-50%);
    box-shadow: 
        0 12px 25px rgba(0, 123, 255, 0.2),
        0 6px 15px rgba(108, 117, 125, 0.15);
}

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

    .portfolio-categories {
        flex-direction: column;
        align-items: center;
    }

    .portfolio-category-btn {
        width: 100%;
        max-width: 300px;
    }
}