session-desktop/stylesheets/_session_theme.scss

// Messages
@import 'themes.scss';

.discussion-container {
  @at-root .light-theme #{&} {
    background-color: $session-color-white;
  }
  @at-root .dark-theme #{&} {
    background-color: $session-shade-2;
  }
}

.conversation {
  background: none !important;
}
.module-conversation-header {
  @at-root .light-theme #{&} {
    background-color: $session-color-white;
  }
  @at-root .dark-theme #{&} {
    background-color: $session-shade-4;
  }
  border-bottom: none;
}

.module-message {
  &__author,
  &__metadata__badge,
  &__metadata__date--incoming,
  &__metadata__date--outgoing {
    @at-root .light-theme #{&} {
      @include session-color-subtle($session-color-black);
    }
    @at-root .dark-theme #{&} {
      @include session-color-subtle($session-color-white);
    }
  }

  &__container--incoming {
    @at-root .light-theme #{&} {
      @include session-color-subtle($session-color-white);
      background-color: $session-shade-8;
    }
    @at-root .dark-theme #{&} {
      background-color: $session-shade-8;
    }
  }

  &__container--outgoing {
    @at-root .light-theme #{&} {
      background-color: $session-color-white;
    }
    @at-root .dark-theme #{&} {
      background-color: $session-shade-11;
    }
  }

  &__container {
    transition: background-color 0.25s;
    box-shadow: 0px 0px 8px 2px rgba(0, 0, 0, 0.69);
  }
}

.message {
  &-highlighted {
    border-radius: 0;

    @at-root .light-theme #{&} {
      background-color: $session-shade-5;
    }
    @at-root .dark-theme #{&} {
      background-color: $session-color-white;
    }
  }

  &-selected {
    .module-message {
      &__container {
        @include themify($themes) {
          background-image: themed('messageSelected');
        }
        box-shadow: $session-dark-shadow;
      }

      &__author {
        color: $session-color-white;
      }
    }
  }

  &-read-receipt-container {
    margin-left: 5px;
  }
}

.inbox {
  @include themify($themes) {
    background: themed('inboxBackground');
  }
}

.conversation {
  background: none !important;
}

.discussion-container {
  background-color: #141414;
}

@mixin session-h-title {
  @include fontAccentBold();
}

h1 {
  @include session-h-title;
  color: $session-shade-16;
  font-size: 25px;
  margin: 0;

  &.active {
    @include themify($themes) {
      color: themed('textColor');
    }
  }
}

h2 {
  @include session-h-title;
  @include themify($themes) {
    color: themed('textColor');
  }
  font-size: 22px;
  text-align: center;
}

h3 {
  @include session-h-title;
  @include themify($themes) {
    color: themed('textColor');
  }
  font-size: 18px;
  padding-top: 22px;
}

h4 {
  @include session-h-title;
  @include themify($themes) {
    color: themed('textColor');
  }
  font-size: 17px;
  text-align: center;
}

.dark-theme .network-status-container .network-status {
  background-color: rgba($session-color-green, 0.6);

  .network-status-message {
    color: $session-color-white;
  }
}