.calibre35 {
height: 50%;
text-align: center;
}
You can't have both of the above lines in the same class. Create another class for the text-align line.
Examples:
<div class="calibre36"><img class="calibre35" src="../images/00033.jpeg"/></div>
.calibre35 {
height: 50%;
width: 50%;
}
.calibre36 {
text-align: center;
}