deletion of the preview page file because it is no longer used

src/css/PagePreview.styl

-.wsFilePreview
-  width 1200px
-  height calc(100% - 85px)
-  &__header
-    background-color previewColor
-    .fa-file-image-o
-      color white
-  &__option
-    &__menu
-      display flex
-      &__addversion
-        padding 8px 15px
-        border 1px solid previewColor
-        border-radius 5px
-        background-color transparent
-        color previewColor
-        cursor pointer
-        & > i
-          margin-left 10px
-        &:hover
-          background-color previewColor
-          border none
-          color white
-  &__contentpage
-    display flex
-    height 100%
-    &__visualizer
-      position relative
-      margin 10px
-      border-radius 10px
-      width 70%
-      height calc(100% - 150px)
-      background-color off-white
-      &__sidebar
-        position absolute
-        top 0
-        right 0
-        width 50px
-        height 100%
-        transition width 1s ease
-        &__visiblepart
-          display flex
-          flex-direction column
-          align-items center
-          border-top-right-radius 10px
-          border-bottom-right-radius 10px
-          width 50px
-          height 100%
-          background-color grey
-          cursor pointer
-          &:hover
-            background-color previewColor
-          &__icon
-            justify-content flex-start
-            font-size 30px
-            color white
-          &__title
-            margin-top 45px
-            color white
-            transform rotate(-90deg)
-        &__propertydetail
-          display none
-      &__dloption
-        display flex
-        margin-left calc(50% - 50px) // 50px => width/2 of the div
-        padding-top 10px
-        width 100px
-        &__icon
-          margin-right 20px
-          font-size 20px
-          cursor pointer
-      &__slidecontainer
-        display flex
-        align-items center
-        width calc(100% - 50px) // 50px => width of sidebar
-        height calc(100% - 40px) // 40px => height of dloption
-        &__fileimg
-          display flex
-          padding 30px
-          width 100%
-          height 100%
-          & > img
-            max-height 100%
-            max-width 100%
-        &__chevron
-          margin 0 5px
-          font-size 20px
-          cursor pointer
-    .timeline
-      margin 10px
-      border-radius 10px
-      width 45%
-      height calc(100% - 150px)
-      background-color off-white
-      overflow scroll
-      &__header
-        border-top-left-radius 10px
-        border-top-right-radius 10px
-        padding 10px 0
-        text-align center
-        font-size 20px
-        color dark-grey
-        background-color grey-hover
-      &__messagelist
-        min-height 300px
-        &__item
-          &__content
-            color dark-grey
-        &__version
-          margin-top 40px
-          background-color grey-hover
-          &__btn
-            padding 5px 25px
-            border-radius 5px
-            width 145px
-            color white
-            font-size 17px
-            background-color previewColor
-            & > i
-              margin-right 10px
-              color dark-grey
-              font-size 22px
-            &:hover
-              background-color lightPreviewColor
-            &:focus
-              background-color lightPreviewColor
-          &__date
-            color fontColor
-            font-size 17px
-      &__texteditor
-        &__simpletext
-          &__input
-            &:focus
-              color htmlColor
-              border-color htmlColor
-        &__submit
-          &__btn
-            border-color htmlColor
-            background-color htmlColor
-            color white
-            &:hover
-              border-color htmlColor
-              background-color htmlColor
-            &:focus
-              border-color htmlColor
-              background-color htmlColor
-
-/***** SENDER RECEIVER *****/
-
-.received
-  .wsFilePreview__contentpage__messagelist__item__content
-      background-color previewColor
-
-/***** ACTIVE SIDEBAR *****/
-
-.activesidebar
-  .wsFilePreview__contentpage__visualizer
-    &__sidebar
-      display flex
-      border-top-right-radius 10px
-      border-bottom-right-radius 10px
-      width 500px
-      background-color off-white
-      &__visiblepart
-        order 1
-        border-top-left-radius 10px
-        border-bottom-left-radius 10px
-        border-top-right-radius 0
-        border-bottom-right-radius 0
-        background-color previewColor
-      &__propertydetail
-        display flex
-        order 2
-        padding 20px
-        overflow-Y auto
-        color previewColor
-
-/****** MEDIA QUERIES ********/
-
-@media (min-width: max-xs) and (max-width: max-lg)
-
-  .wsFilePreview
-    overflow-Y auto
-    &__contentpage
-      display block
-      &__visualizer
-        display flex
-        flex-direction column
-        width calc(100% - 30px) // 20px => margin
-      .timeline
-        width calc(100% - 30px) // 20px => margin
-        &__texteditor
-          &__simpletext
-            display inline-flex
-            display ms-inline-flex
-            width 60%
-          &__submit
-            display inline-flex
-            display ms-inline-flex
-            margin 10px 0
-            &__btn
-              display flex
-              margin-left 35px
-              &__icon
-                margin-left 15px
-
-/**** MEDIA 992px & 1199px ****/
-
-@media (min-width: min-lg) and (max-width: max-lg)
-
-  .wsFilePreview
-    width 900px
-    overflow-Y auto
-
-/******************************/
-
-/**** MEDIA 768px & 991px ****/
-
-@media (min-width: min-md) and (max-width: max-md)
-
-  .wsFilePreview
-    width 100%
-
-/******************************/
-
-/**** MEDIA 576px & 767px ****/
-
-@media (min-width: min-sm) and (max-width: max-sm)
-
-  .wsFilePreview
-    top 69px
-    width 100%
-    height calc(100% - 69px)
-    overflow-Y scroll
-
-/******************************/
-
-/**** MEDIA 575px ****/
-
-@media (max-width: max-xs)
-
-  .activesidebar
-    .wsFilePreview__contentpage__visualizer
-      &__sidebar
-        width 350px
-
-  .wsFilePreview
-    top 69px
-    width 100%
-    height calc(100% - 69px)
-    overflow-Y scroll
-    &__option__menu__addversion
-        padding 8px 5px
-        & > i
-          display none
-    &__contentpage
-      display block
-      &__visualizer
-        display flex
-        flex-direction column
-        width calc(100% - 30px) // 20px => margin
-      .timeline
-        width calc(100% - 30px) // 20px => margin
-        &__texteditor
-          &__simpletext
-            display inline-flex
-            display ms-inline-flex
-            width 60%
-          &__submit
-            display inline-flex
-            display ms-inline-flex
-            margin 10px 0
-            &__btn
-              display flex
-              margin-left 35px
-              &__icon
-                margin-left 15px