.flex-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
}

.flex-container > div {
   width: 450px;
  margin: 10px;
}

#dummy
{
  -moz-border-radius: 5px;
 border-radius: 5px;
    border:solid 1px gray;
    padding:10px;
    background:#555;    
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);

}

#dummy1
{
  -moz-border-radius: 5px;
 border-radius: 5px;
    border:solid 1px gray;
    padding:10px;
    color: #fff;
    background:#666;    
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
}

#dummy2
{
  -moz-border-radius: 5px;
 border-radius: 5px;
    border:solid 1px #000000;
    padding:0px;
    background:#fff;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
}

.polaroid {
  box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
}

.resiz1 {
width: 90%;
max-width: 380px;
height: auto;
}