slack.css

body {
    font-family: sans-serif;
    background: #333; /*black;*/
    color: white;
    font-size: 1.25em;
}
::-webkit-scrollbar { 
    display: none; 
}
.ts {
    display: table-cell;
    width: 5.6em;
    font-family: monospace;
    font-size: 110%;
}
.att {
    padding-left: .5em;
    border-left: 1px solid white;
}
div.msg {
    display: inline;
    white-space: pre-wrap;
    word-wrap: break-word;
}
div.line {
    display: table;
    clear: both;
}
.user {
    font-weight: bold;
}
a, a:visited {
       color: #8888ff;
   }
.att img {
    float: right;
    padding-left: .5em;
    max-height: 200px;
    max-width: 800px;
}
.separator {
    font-size: 125%;
    font-weight: 700;
    text-align: center;
    height: .5em;
    border-bottom: 2px solid white;
    margin-bottom: 1em;
    margin-top: .5em;
}
.separator:first-line {
    height: 1em;
    background-color: black;
}