body {
}
.obrazek{width:320px; height:300px;border-style:double;border-width:5px;border-color:slateblue}
.div1{margin-left:auto;margin-right:auto;width:850px;text-align:center}
.div2 {
    margin-left: auto;
    margin-right: auto;
    width: 600px;
    text-align: center;
}
.div3 {
    margin-left: auto;
    margin-right: auto;
    width: 850px;
    text-align: center;
}
h1 {color: orange}
h2{color: green}
.div4 {
    text-align: center;
    background-color: lightgreen;
    margin-left: auto;
    margin-right: auto;
    width: 900px;
}
#obr_1 {
    width: 290px;
    height: 290px;
}
#obr_2 {
    width: 290px;
    height: 290px;
}
#obr_3 {
    width: 290px;
    height: 290px;
}
.bunka_1{width:300px}
.bunka_1 {width: 600px}