.slider {
    width: 500px;
    height: 500px;
    margin: 40px auto;
    overflow: hidden;
    position: relative;
    border-radius: 12px;
    box-shadow: 0 6px 20px rgba(0,0,0,.15);
}

.slides {
    display: flex;
    height: 100%;     
    transition: transform 0.6s ease;
}

    .slides img {
        width: 500px;
        height: 500px;
        object-fit: cover;
        filter: brightness(.9);
        transition: .4s;
        object-fit: cover; /* keeps image ratio, crops if needed */
        flex-shrink: 0;
    }