header {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
}

h1 {
    color: #f2f7ef;
    text-shadow: 0 0 1px #f2f7ef;
    text-align: center;
    margin: 0 auto;
    margin-bottom: 35px;
}

.gallery-container { 
    line-height: 2;       
    -webkit-column-count: 5;    
    -webkit-column-gap: 15px;
    -moz-column-count: 5;
    -moz-column-gap: 15px;
    column-count: 5;    
    column-gap: 15px;
}  

.gallery-container img {    
   width: 100% !important;    
   height: auto !important;  
}

@media (max-width: 1000px) {
   .gallery-container {
   -moz-column-count:    3;
   -webkit-column-count: 3;
   column-count:         3;
   }
  }  
@media (max-width: 800px) {
   .gallery-container {
   -moz-column-count:    2;
   -webkit-column-count: 2;
   column-count:         2;
   }
  }  
@media (max-width: 400px) {
   .gallery-container {
   -moz-column-count:    1;
   -webkit-column-count: 1;
    column-count:        1;
   }
  }