diff.css

.changed .key,
.added .key,
.removed .key {
    font-weight: 600;
}

.ichanged,
.changed {
    color: #ec971f;
}

.iremoved,
.removed {
    color: #E23E57;
    text-decoration: line-through;
}

.iadded,
.added {
    color: #449d44;
}

.json ul {
    padding-left: 15px;
    margin-left: -5px;
    padding-top: 5px;
    margin-top: -7px;
    list-style-type: none;
    background-image: url(./line.gif);
    background-repeat: repeat-y;
    background-position-y: 13px;
    background-position-x: 0;
}

.json.j-fade li {
    color: #aaa;
}

.json * {
    -webkit-transition: color .05s ease;
       -moz-transition: color .05s ease;
         -o-transition: color .05s ease;
            transition: color .1s ease;
}

.json.line-off ul {
    background-image: none;
}

.json ul[collapsed="on"] {
    background-image: none;
}

.json ul[collapsed="on"] > * {
    display: none;
}

.json ul[collapsed="on"] > *:first-child {
    display: block;
}

.json li {
    margin-top: 1px;
    padding-left: 15px;
}

.json ul:before,
.json ul[collapsed="off"]:before {
    cursor: pointer;
    content: "\f0d7";
    position: absolute;
    font: normal normal normal 14px/1 FontAwesome;
    margin-left: -12px;
    margin-top: 3px;
}

.json ul[collapsed="on"]:before {
    content: "\f0da";
}