element-web/res/css/views/audio_messages/_PlaybackContainer.scss

/*
Copyright 2021 - 2022 The Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

// Dev note: there's no actual component called <PlaybackContainer />. These classes
// are shared amongst multiple voice message components.

// Container for live recording and playback controls
.mx_MediaBody.mx_VoiceMessagePrimaryContainer {
    // The waveform (right) has a 1px padding on it that we want to account for, otherwise
    // inherit from mx_MediaBody
    padding-right: 11px;

    // Cheat at alignment a bit
    display: flex;
    align-items: center;

    contain: content;

    // Waveforms are present in live recording only
    .mx_Waveform {
        .mx_Waveform_bar {
            background-color: $quaternary-content;
            height: 100%;
            /* Variable set by a JS component */
            transform: scaleY(max(0.05, var(--barHeight)));

            &.mx_Waveform_bar_100pct {
                // Small animation to remove the mechanical feel of progress
                transition: background-color 250ms ease;
                background-color: $secondary-content;
            }
        }
    }

    .mx_Clock {
        width: $font-42px; // we're not using a monospace font, so fake it
        min-width: $font-42px; // force sensible layouts in awkward flexboxes (file panel, for example)
        padding-right: 6px; // with the fixed width this ends up as a visual 8px most of the time, as intended.
        padding-left: 8px; // isolate from recording circle / play control
    }

    .mx_RecordingPlayback_timelineLayoutMiddle {
        margin-left: 8px;
        margin-right: 6px;
        position: relative;
        display: inline-block;
        flex: 1;
        height: 30px; // same height as mx_Waveform, needed for automatic vertical centering

        .mx_Waveform {
            left: 0;
            top: 0;
        }

        .mx_SeekBar {
            position: absolute;
            left: 0;
            height: 30px;
            top: -2px; // visually vertically centered

            // Hide the hairline progress bar since we're at 100% height. Need to have distinct rules
            // because CSS is weird.
            background: none;
            &::before {
                background: none;
            }
            &::-moz-range-progress {
                background: none;
            }

            // Make the thumb easier to see. Like the SeekBar original styles, these need to be
            // distinct. We make it transparent so it doesn't show up on the UI, but also larger
            // so it's easier to grab by mouse users in some browsers. Most browsers let the user
            // move and drag the thumb regardless of hitting the thumb, however.
            &::-webkit-slider-thumb {
                width: 10px;
                height: 10px;
                background-color: transparent;
            }
            &::-moz-range-thumb {
                width: 10px;
                height: 10px;
                background-color: transparent;
            }
        }

        // For timeline-rendered playback, the clock is on the other side of the waveform.
        & + .mx_Clock {
            text-align: right;

            // Take the padding off the clock because it's accounted for by the `timelineLayoutMiddle`
            padding: 0;
        }
    }
}