element-web-Github/res/css/views/rooms/_SendMessageComposer.pcss

/*
Copyright 2024 New Vector Ltd.
Copyright 2019 The Matrix.org Foundation C.I.C.

SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
Please see LICENSE files in the repository root for full details.
*/

.mx_SendMessageComposer {
    flex: 1;
    display: flex;
    flex-direction: column;
    font: var(--cpd-font-body-md-regular);
    /* fixed line height to prevent emoji from being taller than text */
    line-height: $font-18px;
    justify-content: center;
    margin-right: 6px;
    /* don't grow wider than available space */
    min-width: 0;

    .mx_BasicMessageComposer {
        flex: 1;
        display: flex;
        flex-direction: column;
        /* min-height at this level so the mx_BasicMessageComposer_input */
        /* still stays vertically centered when less than 55px. */
        /* We also set this to ensure the voice message recording widget */
        /* doesn't cause a jump. */
        min-height: 55px;

        .mx_BasicMessageComposer_input {
            padding: 3px 0;
            /* this will center the contenteditable */
            /* in it's parent vertically */
            /* while keeping the autocomplete at the top */
            /* of the composer. The parent needs to be a flex container for this to work. */
            margin: auto 0;
            /* max-height at this level so autocomplete doesn't get scrolled too */
            max-height: 140px;
            overflow-y: auto;
        }
    }
}