*{
    box-sizing:border-box;
}

body{
    margin:0;
    background:#111;
    font-family:Arial, sans-serif;
    color:white;
}

header{
    position:sticky;
    top:0;
    z-index:100;
    background:#111;
    padding:20px;
    border-bottom:1px solid #222;
}

header h1{
    margin:0;
    font-size:24px;
}

.gallery{
    display:grid;
    grid-template-columns:repeat(auto-fill, minmax(240px, 1fr));
    gap:4px;
    padding:4px;
}

.item{
    position:relative;
    aspect-ratio:1/1;
    overflow:hidden;
    background:#222;
}

.item img{
    width:100%;
    height:100%;
    object-fit:cover;
    cursor:pointer;
    transition:transform .3s ease;
}

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

.lightbox{
    position:fixed;
    inset:0;
    background:rgba(0,0,0,.95);
    display:none;
    align-items:center;
    justify-content:center;
    z-index:999;
    padding:20px;
}

.lightbox.active{
    display:flex;
}

.lightbox-img{
    max-width:95vw;
    max-height:95vh;
    border-radius:12px;
}

.close{
    position:absolute;
    top:20px;
    right:30px;
    font-size:40px;
    cursor:pointer;
    color:white;
}

@media (max-width:700px){

    .gallery{
        grid-template-columns:repeat(3, 1fr);
    }

}