devtools.css

.jsonView{
    margin-left: 20px;
    font-family: Consolas, "Lucida Console", Menlo, "dejavu sans mono", monospace;
    font-size: 16px;
    line-height: 16px;
    padding: 2px;
    cursor: default;
    color: rgb(66, 66, 66);
    white-space: nowrap;
    -webkit-user-select: none;
}

.jsonView>div{
    display: inline-block;
}

.jsonView.hidden{
    display: none;
}

.jsonView>.children, .jsonView.insert{
    display: block;
}

.jsonView>.name{
    color: rgb(136, 19, 145);
}

.jsonView>.separator:before{
    content: ":";
}

.jsonView>.separator{
    padding-right: 5px;
}

.jsonView>.spacing{
    display:inline-block;
    width:15px;
}
.jsonView>.spacing::before{
    content: '1';
    visibility:hidden;
}

.jsonView>.value.null, .jsonView>.value.undefined{
    color: rgb(128, 128, 128);
}

.jsonView>.value.boolean, .jsonView>.value.number{
    color: rgb(28, 0, 207);
}

.jsonView>.value.string:not(.edit):before, .jsonView>.value.string:not(.edit):after{
    content: "\"";
}

.jsonView>.value.string {
    color: rgb(196, 26, 22);
}

.jsonView>.name:hover, .jsonView>.value:hover{
    background-color: rgba(56, 121, 217, 0.1);
}

.jsonView>.expand, .jsonView>.collapse{
    min-width: 20px;
    margin-left: -20px;
    cursor: pointer;
}

.jsonView>.expand:before{
    content: '\25B6';
}

.jsonView>.collapse:before{
    content: '\25BC';
}

.jsonView>.edit{
    padding: 0px 5px 0px 5px;
    white-space: nowrap;
    overflow: hidden;
    background-color: transparent;
}

.jsonView>.edit br{
    display: none;
}

.jsonView>.edit *{
    display: inline;
    white-space: nowrap;
}

.jsonView>.value.edit{
    color: rgb(0, 0, 0);
}

.jsonView>.delete:before{
    content: '+';
    transform: rotate(45deg);
    -webkit-transform: rotate(45deg);
    -o-transform: rotate(45deg);
    -ms-transform: rotate(45deg);
    display: inline-block;
}

.jsonView>.delete{
    opacity: 0;
    display: inline;
    padding: 3px;
    cursor: pointer;
    color: rgb(150, 150, 150);
}

.jsonView>.item:hover~.delete{
    opacity: 1;
    color: rgb(150, 150, 150);
}
.jsonView>.delete:hover{
    opacity: 1;
    color: rgb(0, 0, 0);
    background: rgb(220, 220, 220);
}

.jsonView.readonly>.insert,.jsonView.readonly>.delete{
    display: none !important;
}
.jsonView>.insert:before{
    content: '+';
}

.jsonView>.insert{
    display: none;
    color: rgb(150, 150, 150);
    cursor: pointer;
}

.jsonView.expanded>.insert, .jsonView.expanded>.insert{
    display: inline-block;
    margin-left: 20px;
    padding: 3px;
}

.jsonView>.insert:hover{
    color: rgb(0, 0, 0);
    background: rgb(220, 220, 220);
}