one-dark/cinnamon/sass/ui/notify.scss

//
// Notifications
//
#notification {
  border: 1px solid $borders_color;
  border-radius: 3px;
  background-color: $bg_color;
  padding: 13px;
  spacing-rows: 10px;
  spacing-columns: 10px;
  margin-from-right-edge-of-screen: 20px;
  width: 34em;
  color: $fg_color;

  .popup-menu & {
    color: $fg_color;
    border-image: url('assets/misc/message.svg') 9 9 9 9;

    .notification-button,
    .notification-icon-button {
      @extend %button;
      padding: 5px;
    }

    StEntry {
      @extend %entry;
    }
  }

  &.multi-line-notification {
    padding-bottom: 13px;
    color: $fg_color;
  }

  &-scrollview {
    max-height: 10em;

    > .top-shadow,
    > .bottom-shadow {
      height: 1em;
    }

    &:ltr > StScrollBar {
      padding-left: 6px;
    }
    &:rtl > StScrollBar {
      padding-right: 6px;
    }
  }

  &-body {
    spacing: 5px;
  }
  &-actions {
    spacing: 10px;
  }
}

.notification {
  &-with-image {
    min-height: 159px;
    color: $fg_color;
  }

  &-button,
  &-icon-button {
    @extend %button;
    padding: 5px;
  }

  &-icon-button > StIcon {
    icon-size: 32px;
  }

  StEntry {
    @extend %osd_entry;
  }
}