* {
    box-sizing: border-box;
}

.column {
    float: left;
    width: 25%;
    padding: 10px;
}

.column img {
    opacity: 0.8;
    cursor: pointer;
}

.column img:hover {
    opacity: 1;
}

.row:after {
    content: "";
    display: table;
    clear: both;
}

.container {
    display: none;
    position: fixed;
    left: 0;
    top: 0;
    z-index: 100;
    width: 100%;
    min-height:20%;
    max-height:100%;
    margin: auto;
}

#imgtext {
    position: absolute;
    bottom: 15px;
    left: 15px;
    color: royalblue;
    font-size: 50px;
}

.closebtn {
    position: absolute;
    top: 10px;
    right: 15px;
    color: blue;
    font-size: 35px;
    cursor: pointer;
}

#plachta{
    height: 2000px;
    width: 100%;
    background-color:#666666;
    z-index: -2;
    position: fixed;
    left: 0;
    top: 0;
}
@media (max-width: 600px) {

img{
    height: 100px;
}
}
@media (max-width: 900px) and (min-width: 600px) {
img{
    height: 150px;
}
}
@media (min-width: 1300px) {

img{
    height: 300px;
}
}
@media (max-width: 1300px) and (min-width: 900px) {
img{
    height: 200px;
}