css

/* COLLAGE IMAGE LAYOUT - BORDER INSTRUCTIONS
Here, you only need to change the "border" value, which by default is "3px solid white;".
If you want no border at all, replace "3px solid white;" with "none;".
If you want to decrease the size of the border, you could do "1px solid white;"
*/

.Collage img,
.Collage figure .blur {
  border: 1px solid white;
}