borders around and between pictures

for example – you can add this to your nggallery.css:

.ngg-widget img {
    border: 2px solid #000;
    margin-right: 7px;
}

.ngg-gallery-thumbnail-box,
.ngg-widget img {
-moz-transition:-moz-transform 0.1s ease-in;
-webkit-transition:-webkit-transform 0.1s ease-in;
-o-transition:-o-transform 0.1s ease-in;
-ms-transition:-ms-transform 0.1s ease-in;
}

.ngg-widget img:hover,
.ngg-gallery-thumbnail-box:hover {
-moz-transform:scale(1.25);
-webkit-transform:scale(1.25);
-o-transform:scale(1.25);
-ms-transform:scale(1.25);
z-index:10000;
position:relative;
}