framework/less/forum/NotificationList.less

.NotificationList {
  overflow: hidden;

  &-header {
    @media @tablet-up {
      padding: 12px 15px;
      border-bottom: 1px solid @control-bg;

      display: flex;
      justify-content: space-between;
      align-items: center;

      h4 {
        font-size: 12px;
        text-transform: uppercase;
        font-weight: bold;
        margin: 0;
        color: @muted-color;
      }
    }

    // Mark all as read button
    .Button {
      padding: 0;
      text-decoration: none;

      // The NotificationList may be displayed inside of the drawer as a
      // dropdown menu – but the drawer may have .light-contents() applied to
      // it. In this case we will need to reset the button's styles back to
      // normal.
      & when (@config-colored-header = true) {
        color: @control-color;

        &:hover,
        &:focus {
          color: @link-color;
        }
      }

      .add-keyboard-focus-ring();
      .add-keyboard-focus-ring-offset(4px);

      .icon {
        margin-right: 0;
      }
    }
  }

  // Message displayed when notifications are empty
  &-empty {
    color: @muted-color;
    text-align: center;
    padding: 50px 0;
    font-size: 16px;
  }
}

.NotificationGroup {
  border-top: 1px solid @control-bg;
  margin-top: -1px;

  &:not(:last-child) {
    margin-bottom: 20px;
  }

  &-header {
    font-weight: bold;
    color: @heading-color !important;
    padding: 8px 16px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;

    display: flex;
    align-items: center;

    // Prevent outline overflowing parent
    .add-keyboard-focus-ring-offset(-1px);
  }

  &-badges {
    @overlap: 13px;

    margin-right: 8px;
    padding-right: @overlap;

    .Badge {
      margin-right: -@overlap;
      position: relative;
      .Badge--size(21px);
    }
  }

  &-content {
    list-style: none;
    margin: 0;
    padding: 0;
  }
}

.Notification {
  padding: 8px 16px;
  color: @muted-color !important; // required to override .light-contents applied to header
  overflow: hidden;

  display: grid;
  grid-template-columns: auto auto 1fr auto;

  grid-template-areas:
    "avatar icon title   button"
    "x      x    excerpt excerpt";

  align-items: baseline;
  row-gap: 1px;
  column-gap: 6px;

  // Prevent outline overflowing parent
  .add-keyboard-focus-ring-offset(-1px);

  &.unread {
    background: @control-bg;
  }

  &:hover,
  &:focus,
  &:focus-within {
    text-decoration: none;
    background: @control-bg;

    .Notification-action {
      opacity: 1;
    }
  }

  .Avatar {
    .Avatar--size(24px);
    grid-area: avatar;
  }
  
  // Since images don't have baselines, aligning against the baseline won't work.
  // Instead we need to do some manual hackery to fix then, otherwise they won't
  // be correctly vertically aligned.
  img.Avatar {
    align-self: flex-start;
    margin-top: -2px;
  }

  &-icon {
    font-size: 14px;
    grid-area: icon;
  }

  &-title {
    grid-area: title;
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    align-items: baseline;
  }

  &-content {
    line-height: 19px;
    margin-right: 8px;

    .username {
      font-weight: bold;
    }
  }

  time {
    line-height: inherit;
    font-size: 11px;
    line-height: 19px;
    font-weight: bold;
    text-transform: uppercase;
  }

  &-action {
    line-height: inherit;
    padding: 0;
    opacity: 0;

    .add-keyboard-focus-ring();
    .add-keyboard-focus-ring-offset(4px);

    grid-area: button;

    // Needs more specificity to fix hover/focus styles not applying in dropdown
    .Notification & when (@config-colored-header = true) {
      color: @control-color;

      &:hover,
      &:focus {
        color: @link-color;
      }
    }

    .icon {
      font-size: 13px;
      margin-right: 0;
    }
  }

  &-excerpt {
    grid-area: excerpt;
    color: @muted-more-color;
    font-size: 11px;
    white-space: nowrap;
    text-overflow: ellipsis;
    overflow: hidden;
  }
}