discourse/app/assets/stylesheets/desktop/topic-timeline.scss

.timeline-loading {
  width: 900px;
}

.composer-open {
  .topic-timeline {
    opacity: 0;
  }
}

.timeline-container {
  box-sizing: border-box;
  z-index: 499;
  margin-left: 757px;

  @media all and (min-width: 1140px) {
    margin-left: 820px;
  }
  @media all and (min-width: 1250px) {
    margin-left: 900px;
  }

  position: fixed;
  -webkit-transform: translate3d(0,0,0);

  &.timeline-docked {
    position: absolute;
  }

  &.timeline-docked-bottom {
    .timeline-footer-controls {
      opacity: 0;
    }
  }

  .topic-timeline {
    margin-left: 3em;
    width: 150px;
    transition: opacity 0.2s ease-in;

    .timeline-controls {
      margin-bottom: 1em;
    }

    .timeline-footer-controls {
      margin-top: 1em;
      line-height: 2.5em;
      transition: opacity 0.2s ease-in;

      button {
        margin-right: 0.5em;
      }

      ul.dropdown-menu {
        right: 0.5em;
        top: auto;
        bottom: 25px;
        left: auto;
      }
    }

    .start-date {
      @include unselectable;
      color: dark-light-choose(scale-color($primary, $lightness: 50%), scale-color($secondary, $lightness: 50%));
    }

    .timeline-scrollarea {
      margin-top: 0.5em;
      margin-left: 0.5em;
      border-left: 1px solid;
      border-color: dark-light-choose(scale-color($tertiary, $lightness: 80%), scale-color($tertiary, $lightness: 20%));
      position: relative;
      -webkit-transform: translate3d(0,0,0);
    }

    .timeline-padding {
      transition: height 0.15s ease-out;
      cursor: pointer;
      .widget-dragging & {
        transition: none;
      }
    }

    .timeline-handle {
      @include border-radius-all(0.8em);
      width: 0.35em;
      background-color: dark-light-choose(scale-color($tertiary, $lightness: 80%), scale-color($tertiary, $lightness: 20%));
      height: 100%;
      float: left;
    }

    .timeline-scroller-content {
      padding-left: 1em;
    }

    .timeline-ago {
      color: dark-light-choose(scale-color($primary, $lightness: 50%), scale-color($secondary, $lightness: 50%));
    }

    .timeline-scroller {
      @include unselectable;
      margin-left: -0.19em;
      cursor: ns-resize;
      display: flex;
      align-items: center;
    }

    .timeline-replies {
      font-weight: bold;
    }

    .timeline-last-read {
      position: absolute;
      margin-left: -0.19em;

      .btn-small {
        padding: 2px 5px;
      }

      i.progress {
        font-size: 0.5em;
        color: dark-light-choose(scale-color($tertiary, $lightness: 80%), scale-color($tertiary, $lightness: 20%));
        margin-right: 1em;
      }
    }

    .now-date {
      @include unselectable;
      display: inline-block;
      color: dark-light-choose(scale-color($primary, $lightness: 50%), scale-color($secondary, $lightness: 50%));
      margin-top: 0.5em;
      i {
        margin-left: 0.15em;
      }
    }
  }
}