svg.css

.link {
    fill: none;
    stroke: #666;
    stroke-width: 1.5px;
    opacity: .7;
    marker-end: url(#end);
    
    transition: opacity 250ms;
    -webkit-transition: opacity 250ms;
    -moz-transition: opacity 250ms;
}

marker#end {
    fill: #666;
    stroke: #666;
    stroke-width: 1.5px;
}

.node rect {
    stroke-width: 1.5px;
    
    transition: opacity 250ms;
    -webkit-transition: opacity 250ms;
    -moz-transition: opacity 250ms;
}

.node text {
    fill: #000;
    font: 10px sans-serif;
    pointer-events: none;
}

.node.selected rect {
    filter: url(#blue-glow);
}

.link.inactive,
.node.inactive rect,
.node.inactive text {
    opacity: .2;
}

.node.inactive.selected rect,
.node.inactive.selected text {
    opacity: .6;
}

.legend {
    position: fixed;
}

.legend .category rect {
    stroke-width: 1px;
}

.legend .category text {
    fill: #000;
    font: 10px sans-serif;
    pointer-events: none;
}