JSONView Chrome extension Afterglow theme https://github.com/gildas-lormeau/JSONView-for-Chrome

afterglow.css

body {
  white-space: pre;
  font-family: monospace;
  font-size: 13px;
  background-color: #2e2e2e;
  color: #d6d6d6;
}

a {
  color: #b4c973;
}

.property {
  font-weight: normal;
}

.type-null {
  color: #a1617a;
}

.type-boolean {
  color: #cc7833;
}

.type-number {
  color: #6d9cbe;
}

.type-string {
  color: #b4c973;
}

.callback-function {
  color: #ffc66d;
}

.collapser:after {
  content: "-";
}

.collapsed > .collapser:after {
  content: "+";
}

.ellipsis:after {
  content: " … ";
}

.collapsible {
  margin-left: 2em;
}

.hoverable {
  padding-top: 1px;
  padding-bottom: 1px;
  padding-left: 2px;
  padding-right: 2px;
  border-radius: 2px;
}

.hovered {
  background-color: #404040;  
}

.collapser {
  padding-right: 6px;
  padding-left: 6px;
}