usrspace-browser-addon/popup/index.css

body {
    width: 360px;
}

h2 {
    margin: 12px 8px 8px;
}

.panel-list-item > .icon {
    text-align: center;
    width: 23px;
    margin-right: 4px;
}
.panel-list-item > .icon > img {
    vertical-align: text-bottom;
}

#calendar {
    margin: 0 8px;
}
#calendar > img {
    vertical-align: text-bottom;
    margin-right: 4px;
}

#space-api {
    margin: 0;
    padding: 0 8px;
    height: 128px;
    overflow-x: hidden;
    overflow-y: scroll;
    background-color: #ebebeb;
}
#space-api code {
    font-family: monospace;
    font-size: 10px;
}