custom.css

/* Sidebar color */
.X9KLPc {
    background-color: #093a89;
}

/* Sidebar elemtents bg color when hovering */
.PL5Wwe:focus:not(.dQ2Tsf),
.PL5Wwe:hover:not(.dQ2Tsf),
.tuKyod .LoYJxb {
    background-color: #032151;
}

/* Sidebar elements text color for chans with unread messages */
.PL5Wwe.H7du2 .t5F5nf {
    color: #fff;
}

/* Channel name color in sidebar */
.t5F5nf {
    color: rgb(202, 196, 201);
}


/* Sidebar "recent" or "starred" section names color */
.aOHsTc {
    color: rgb(202, 196, 201);
}

/* Sidebar Search section text color */
.HLTcjb {
    color: rgb(202, 196, 201);
}
.D3DXDc {
    fill: rgb(202, 196, 201) !important;
}

/* Sidebar search button hovering bg color */
.GbZFNe:focus, .GbZFNe:hover {
    background-color: #032151;
}

/* Search Menu bg color */
.yoV6yd {
    background-color: #093a89;
}

/* Search menu text color */
.Uk0Bfe .zHQkBf, .Uk0Bfe .snByac, .dQ2Tsf .NXfF8b, .dQ2Tsf .ZTmjQb {
    color: #000;
}

.ndJi5d {
    rgba(0,0,0,0.38);
}

/* Search menu elements colors when hovering */
.dQ2Tsf[aria-selected="true"], .PL5Wwe:hover > .dQ2Tsf {
    background-color: #eee;
    color: #fff
}

/* Search menu people list mail color */
.dQ2Tsf[aria-selected="true"] .Kfe2Ub, .PL5Wwe:hover > .dQ2Tsf .Kfe2Ub {
    color: #000;
}

/* Top left corner section (with title) background color */
.Riuhhf {
    background-color: #093a89;
}

/* Chat top left logo text color */
#XMLID_8_-Clipped{
    opacity: 0.8 !important;
    fill: #fff !important;
}

/* Time and menu buttons and clock for channels inactive and active colors */
.sFuxxd {
    color: rgb(202, 196, 201);
}
.PL5Wwe.H7du2 .sFuxxd {
    color: #fff;
}
.DQy0Rb {
    fill: rgb(202, 196, 201) !important;
}
.PL5Wwe.H7du2 .DQy0Rb {
    fill: #fff !important;
}
.QeRfYe {
    fill: rgb(202, 196, 201) !important;
}
.PL5Wwe.H7du2 .QeRfYe {
    fill: #fff !important;
}

/* Make code snippets have slack colors */
.FMTudf {
    border: 1px solid #e0e0e0;
    background: #f9f9f9;
}

/* Make inline pre have slack colors */
.U8d2H {
    background-color: #f7f7f9;
    color: #d72b3f;
}
/* Specify size for thread links */
.threadlink {
    font-size: 8px;
}

/* Reduce left and right margins in the chat area */
.BEjUKc .cFc9ae {
    margin-left: 10px;
    margin-right: 10px;
    width: auto;
    max-width:none;
}
.Bl2pUd {
    padding-left: 0px;
    padding-right: 0px;
}

/* Reduce height of header bar */
.DWzK6d, .gb_Uf > .gb_g, .gb_Uf, .Jrbdv {
    height: 45px;
}

/* Reduce whitespace around New conversation button */
.RnpT2b {
    margin: 4px 0 4px 0;
    min-height: 0px;
}
.IEIJqd {
    padding-top: 0;
}

/* Allow messages to display full-width */
.bzJiD .jGyvbd .QIJiHb, .bzJiD .jGyvbd .zX644e {
    max-width: none;
}

/* Reduce top and bottom padding around date */
.mCOR5e {
    padding: 10px 0 0px 0;
}

/* Reduce right margin in sidebar */
.n5yyEc {
    margin-right: 4px;
}

/* Sidebar "recent" or "starred" section names text size */
.aOHsTc {
    font-size: 16px;
    margin-left: 16px;
}

/* Search Menu shape and dimensions */
.yoV6yd {
    margin-top: -4px;
    width: 100%;
    border-radius: 0px;
    -moz-border-radius: 0px
}

/* Search Menu "frequent" section text color and size */
.wAR34c {
    font-size: 16px;
}

/* Padding height between messages in a thread */
.nF6pT {
    padding-top: 4px;
}

/* Margins around Unread label */
.YQsadf {
    min-height: 20px;
}

/* Sidebar "recent" or "starred" section title padding height */
.wJNchb, .nFzS9e {
    margin-top: 10px;
}

/* Draw white line between the sidebar sections and reduce padding */
.PL5Wwe + .wJNchb, .teTAFe:not(.fXx9Lc) + .vHL80e .aOHsTc {
    border-top: solid 1px #e0e0e0;
    padding-top: 6px;
}

/* Sidebar channels elements height */
.LoYJxb {
    height: 26px;
}


/* Vertically align triple dots buttons on
channels in sidebar with the new height */
.MhXXcc {
    line-height: 26px;
}
.gsrV1e {
    height: 22px;
    width: 22px;
}
.QeRfYe .Lw7GHd {
    margin: 2px 6px 0 6px;
}

/* Big emojis size */
.Zc1Emd.NM3Nfc {
    font-size: 24px;
}

/* Inline emojis size */
img {
    border: none;
    font-size: 1.3em !important;
}

/* Reduce top margin in thread block */
.dsoUjb {
    padding: 8px 0;
}

/* Reduce size of reply button */
.dCMjy {
    width: 20px;
    min-width: 20px;
    height: 20px;
    min-height: 20px;
    margin-right: 36px;
}

/* Reduce space around blue NEW alert */
.k1lILc {
    padding: 5px 0 0;
}
.k1lILc + .ajCeRb {
    padding-top: 5px;
}

/* Reduce space between thread blocks */
.cZICLc {
    margin-top: 6px;
}

/* Increase boldness of usenames in conversations */
.Z4BnXb {
    font-weight: 900;
}

/* Make code snippets look like slack's */
.FMTudf {
    font-family: Monaco,Menlo,Consolas,"Courier New",monospace !important;
    font-size: .75rem;
    margin: 1px 0;
    padding: 3px 10px;
    -webkit-border-radius: 4px;
    -moz-border-radius: 4px;
    border-radius: 4px;
}

/* Reduce the height of collapsed message row */
.zh742e {
    padding-top: 0;
}

/* Reduce margin around reaction emojis */
.SFMExc, .FIgEvc {
    margin-top: 0;
    margin-bottom: 0;
}

/* Reduce margin around link previews */
.V5MAMb {
    margin-top: 0;
    margin-bottom: 0;
}

/* Reduce size of youtube previews */
.uXftcc, .CXTVff {
    height: 240px;
    background-size: auto 240px;
}
.uXftcc {
    width: 320px;
}

/* Reduce size of youtube videos */
.uXftcc > .gntfhc, .CXTVff > .gntfhc {
    height: 240px;
    width: auto;
}

/* Reduce margin below lowest message in thread */
.jGyvbd > .nF6pT:last-child, .zh742e:last-child {
    padding-bottom: 10px;
}

/* Make inline pre look like slack's */
.U8d2H {
    font-family: Monaco,Menlo,Consolas,"Courier New",monospace !important;
    margin: 0px;
    padding: 1px 3px;
    -webkit-border-radius: 3px;
    -moz-border-radius: 3px;
    border-radius: 3px;
}

/* Reduce sidebar width */
.X9KLPc, .Riuhhf {
    width: 280px
}

/* Reduce margin above "Starred" label */
.aOHsTc {
    margin-top: 5px;
}

/* Fix emojis dimensions */
.iiJ4W {
    height: auto;
    width: auto;
    max-height: 1.2em;
    max-width: 1.2em;
    min-width: auto;
}

/* Reduce size of New conv button */
.SfqTBc {
    padding: 4px 18px 4px 12px;
    min-height: 30px;
}

/* Reduce height of link and file previews */
.Pj9rof { /* global block */
    height: 140px;
    width: 500px;
}
.tHcB6b { /* image container */
    height: 100px;
}
.rNTKFb { /* image (for files) */
    height: 100px;
}
.kmatHb { /* text */
    font-size: 12px;
    line-height: 13px;
}
.SXFjfb { /* text container */
    height: 40px;
    padding-top: 3px;
    padding-left: 15px;
}
.VEWZeb { /* icon next to text */
    height: 16px;
    margin-right: 0px;
    margin-top: 2px;
}
.SXFjfb.DoYruc { /* text when there is also a link */
    padding-top: 3px;
}
.rNTKFb.Tvakkc, .tHcB6b .wU0G2b, .rNTKFb.Tvakkc + .bBukm /* image (for links) */ {
    height: 100px !important;
    width: auto !important;
}