html, body {
    padding: 0;
    margin: 0;
}


/* ------------------------------------------------------------------------------*/
.gallery {
    position: relative;
    left: 0;
    display: flex;
    flex-direction: row;
    justify-content: center;
    background-color: tomato;
}

.container {
    background-color: violet;
    margin: 1%;
}

.thumb {
    max-height: 171px;
}

.helper {
    height: 100%;
    display: inline-block;
    vertical-align: middle;
}

.lightbox {
    position: fixed;
    z-index: 999;
    height: 0;
    width: 0;
    text-align: center;
    top: 0;
    left: 0;
    background: rgba(0, 0, 0, 0.8);
}

.lightbox img {
    position: relative;
    max-width: 60%;
    max-height: 80%;

    clip-path: inset(0,0,100%,0); 
    transition: clip-path 1s;
}

.lightbox:target {
    /** Remove default browser outline */
    outline: none;    

    width: 100%;
    height: 100%;
}

.lightbox:target img {
    border: none;
    vertical-align: middle;

    clip-path: inset(0,0,50%,0); 
    transition: clip-path 1s;
}

.light-btn {
    color: #fafafa;
    background-color: #333;
    border: solid 3px #777;
    padding: 5px 15px;
    border-radius: 1px;
    text-decoration: none;
    cursor: pointer;
    vertical-align: middle;
    position: absolute;
    top: 45%;
    z-index: 99;
}

.light-btn:hover {
    background-color: #111;
}

.btn-prev {
    left: 7%;
}

.btn-next {
    right: 7%;
}

.btn-close {
    position: absolute;
    right: 2%;
    top: 2%;
    color: #fafafa;
    background-color: #92001d;
    border: solid 5px #ef4036;
    padding: 10px 15px;
    border-radius: 1px;
    text-decoration: none;
}

.btn-close:hover {
    background-color: #740404;
}