element-web/res/css/views/elements/_RichText.scss

// XXX: bleurgh, what is this? These classes totally break the component
// naming scheme; it's completely unclear where or how they're being used
// --Matthew

.mx_UserPill,
.mx_RoomPill,
.mx_GroupPill,
.mx_AtRoomPill {
    display: inline-flex;
    align-items: center;
    vertical-align: middle;
    border-radius: $font-16px;
    line-height: $font-15px;
    padding-left: 0;
    padding-right: $font-5px;
}

a.mx_Pill {
    text-overflow: ellipsis;
    white-space: nowrap;
    overflow: hidden;
    vertical-align: text-bottom;
    max-width: calc(100% - 1ch);
}

.mx_Pill {
    padding: $font-1px;
}

/* More specific to override `.markdown-body a` color */
.mx_EventTile_content .markdown-body a.mx_GroupPill,
.mx_GroupPill {
    color: $accent-fg-color;
    background-color: $rte-group-pill-color;
}

/* More specific to override `.markdown-body a` text-decoration */
.mx_EventTile_content .markdown-body a.mx_Pill {
    text-decoration: none;
}

/* More specific to override `.markdown-body a` color */
.mx_EventTile_content .markdown-body a.mx_UserPill,
.mx_UserPill {
    color: $primary-fg-color;
    background-color: $other-user-pill-bg-color;
}

.mx_UserPill_selected {
    background-color: $accent-color !important;
}

/* More specific to override `.markdown-body a` color */
.mx_EventTile_highlight .mx_EventTile_content .markdown-body a.mx_UserPill_me,
.mx_EventTile_content .markdown-body a.mx_AtRoomPill,
.mx_EventTile_content .mx_AtRoomPill,
.mx_MessageComposer_input .mx_AtRoomPill {
    color: $accent-fg-color;
    background-color: $mention-user-pill-bg-color;
}

/* More specific to override `.markdown-body a` color */
.mx_EventTile_content .markdown-body a.mx_RoomPill,
.mx_EventTile_content .markdown-body a.mx_GroupPill,
.mx_RoomPill,
.mx_GroupPill {
    color: $accent-fg-color;
    background-color: $rte-room-pill-color;
}

.mx_EventTile_body .mx_UserPill,
.mx_EventTile_body .mx_RoomPill,
.mx_EventTile_body .mx_GroupPill {
    cursor: pointer;
}

.mx_UserPill .mx_BaseAvatar,
.mx_RoomPill .mx_BaseAvatar,
.mx_GroupPill .mx_BaseAvatar,
.mx_AtRoomPill .mx_BaseAvatar {
    position: relative;
    display: inline-flex;
    align-items: center;
    border-radius: 10rem;
    margin-right: 0.24rem;
}

.mx_Markdown_BOLD {
    font-weight: bold;
}

.mx_Markdown_ITALIC {
    font-style: italic;
    /*
    // interestingly, *not* using the explicit italic font
    // variant seems yield better results.

    // compensate for Nunito italics being terrible
    // https://github.com/google/fonts/issues/1726
    transform: skewX(-14deg);
    display: inline-block;
    */
}

.mx_Markdown_CODE {
    padding: .2em 0;
    margin: 0;
    font-size: 85%;
    background-color: $rte-code-bg-color;
    border-radius: 3px;
}

.mx_Markdown_HR {
    display: block;
    background: $rte-bg-color;
}

.mx_Markdown_STRIKETHROUGH {
    text-decoration: line-through;
}