converse.js/sass/_chatrooms.scss

#conversejs.converse-embedded,
#conversejs {
    .add-chatroom {
        input[type="submit"],
        input[type="button"] {
            margin: 0.3em 0;
        }
    }

    .chat-head-chatroom {
        background-color: $chatroom-head-color;

        .chatroom-description {
            color: lighten($chatroom-head-color, 25%);
            font-size: $font-size-large;
            font-size: 70%;
            margin-top: 3px;
            overflow-y: hidden;
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
        }

        a, a:visited, a:hover, a:not([href]):not([tabindex]) {
            &.chatbox-btn {
                &.fa {
                    color: $chat-head-text-color;
                    &.button-on:before {
                        color: $chatroom-head-color;
                    }
                }
            }
        }

        .chatbox-btn {
            &.button-on:before {
                color: $chatroom-head-color;
            }
        }
        .chat-title {
            .chatroom-jid {
                font-size: $font-size-small;
            }
        }
    }

    .chatroom {
        width: $chatroom-width;
        @media screen and (max-height: $mobile-landscape-height){
            width: $mobile-chat-width;
        }
        @media screen and (max-width: $mobile-portrait-length) {
            width: $mobile-chat-width;
        }

        .box-flyout {
            overflow-y: hidden;
            background-color: $chatroom-head-color;

            width: 100%;
            @media screen and (max-height: $mobile-landscape-height) {
                height: $mobile-chat-height;
                width: $mobile-chat-width;
                height: 100vh;
            }
            @media screen and (max-width: $mobile-portrait-length) {
                height: $mobile-chat-height;
                width: $mobile-chat-width;
                height: 100vh;
            }
            .chatroom-body {
                flex-direction: row;
                flex-flow: nowrap;
                @include border-bottom-radius($chatbox-border-radius);
                background-color: white;
                border-top: 0;
                width: 100%;
                overflow: hidden;

                .row {
                    flex-direction: row;
                }
                .chat-topic {
                    font-weight: bold;
                    color: $chatroom-head-color;
                }
                .chat-info {
                    color: $chatroom-head-color;
                    line-height: normal;
                    &.badge {
                        color: $chat-head-text-color;
                    }
                }
                .mentioned {
                    font-weight: bold;
                }
                .disconnect-msg {
                    padding: 2em 2em 0 2em;
                }
                .chat-area {
                    display: flex;
                    flex-direction: column;
                    word-wrap: break-word; 
                    min-width: $chat-width;
                    .new-msgs-indicator {
                        background-color: $chatroom-head-color;
                    }
                    .chat-content {
                        height: 100%;
                    }
                    &.full {
                        min-width: 100%;
                    }
                }
                .occupants {
                    display: flex;
                    flex-direction: column;
                    justify-content: space-between;
                    overflow-x: hidden;
                    overflow-y: hidden;
                    vertical-align: top;
                    background-color: white;
                    border-left: 1px solid $text-color;
                    border-bottom-right-radius: $chatbox-border-radius;
                    padding: 0.5em;

                    .occupants-heading {
                        font-family: $heading-font; 
                        padding: 0.3em 0;
                    }

                    .chatroom-features {
                        width: 100%;
                        .feature {
                            float: left;
                            margin-right: 0.5em;
                            padding-right: 0;
                            font-size: 1em;
                            cursor: help;
                        }
                    }
                    .awesomplete {
                        ul {
                            padding: 0;
                            li {
                                padding: .5em;
                            }
                        }
                    }
                    ul {
                        padding: 0.5em 0 0 0;
                        margin-bottom: 0.5em;
                        overflow-x: hidden;
                        overflow-y: auto;
                        list-style: none;

                        &.occupant-list {
                            overflow-y: auto;
                            flex-basis: 0;
                            flex-grow: 1;
                            border-bottom: 1px solid lightgrey;
                        }
                        &.features-list {
                            padding-top: 0;
                            .feature {
                                width: 100%;
                                .fa {
                                    color: $text-color;
                                }
                            }
                        }
                        li {
                            cursor: default;
                            display: block;
                            font-size: $font-size-small;
                            overflow: hidden;
                            padding: 0.25em 0.25em 0.25em 0;
                            text-overflow: ellipsis;
                            .fa {
                                margin-right: 0.5em;
                            }
                            &.feature {
                                font-size: $font-size-tiny;
                            }
                            &.occupant {
                                cursor: pointer;

                                div.row.no-gutters {
                                    flex-wrap: nowrap;
                                    min-height: 1.5em;
                                }
                                .badge {
                                    margin-bottom: 0.125rem;
                                }

                                .occupant-status {
                                    display: inline-block;
                                    margin: 0 0.5em 0.125em 0;
                                    width: 0.5em;
                                    height: 0.5em;

                                    &.occupant-online,
                                    &.occupant-chat {
                                        background-color: #1A9707;
                                    }
                                    &.occupant-dnd {
                                        background-color: red;
                                    }
                                    &.occupant-away {
                                        background-color: darkorange;
                                    }
                                    &.occupant-xa {
                                        background-color: orange;
                                    }
                                    &.occupant-offline {
                                        background-color: darkgrey;
                                    }
                                }
                            }
                        }
                    }
                }
                .chatroom-form-container {
                    background-color: white;
                    border-bottom-left-radius: $chatbox-border-radius;
                    border-bottom-right-radius: $chatbox-border-radius;
                    border: 0;
                    color: $text-color;
                    font-size: $font-size;
                    height: 100%;
                    width: 100%;
                    overflow-y: auto;

                    .validation-message {
                        font-size: 90%;
                        color: $error-color;
                    }
                    .chatroom-form {
                        label,
                        input[type=text] {
                            display: block;
                        }
                    }
                    input[type=button],
                    input[type=submit] {
                        margin: 0 0.5em;
                    }
                    .button-primary {
                        background-color: $chatroom-head-color;
                    }
                }
            }
        }

        .sendXMPPMessage {
            .chat-toolbar {
                background-color: white;
                border-top: 8px solid $chatroom-head-color;
                color: $chatroom-head-color;
                .fa, .fa:hover {
                    color: $chatroom-head-color;
                }
            }
            .chat-textarea {
                border-bottom-right-radius: 0;
            }
            .send-button {
                background-color: $chatroom-head-color;
            }
        }

        .room-invite {
            .invited-contact {
                margin: -1px 0 0 -1px;
                width: 100%;
                border: 1px solid #999;
            }
        }
    }
}

@media screen and (max-width: 767px) {
    #conversejs:not(.converse-embedded)  {
        .chatbox {
            .box-flyout {
                .chatroom-body {
                    .chat-area {
                    }
                }
            }
        }
    }
}