remove editor preview css styles from mobile

app/assets/stylesheets/mobile/compose.scss

@@ -213,25 +213,9 @@ display: none;
     #wmd-input:disabled {
       background-color: scale-color($primary, $lightness: 75%);
     }
-    #wmd-input, #wmd-preview {
+    #wmd-input {
       color: darken($primary, 40%);
     }
-    #wmd-preview {
-      border: 1px dashed scale-color-diff();
-      overflow: auto;
-      visibility: visible;
-      video {
-        max-width: 100%;
-        height: auto;
-      }
-      audio {
-        max-width: 100%;
-      }
-      &.hidden {
-        width: 0;
-        visibility: hidden;
-      }
-    }
     #wmd-input {
       bottom: 35px;
     }
@@ -272,19 +256,7 @@ display: none;
 }
 
 #reply-control {
-  &.hide-preview {
-    .wmd-controls {
-      #wmd-input {
-        width: 100%;
-      }
-      .preview-wrapper {
-        display: none;
-      }
-      .textarea-wrapper {
-        width: 100%;
-      }
-    }
-  }
+
   .wmd-controls {
     left: 10px;
     right: 10px;
@@ -293,13 +265,8 @@ display: none;
     bottom: 54px;
     display: block;
 
-    // this removes the topmost margin;
-    // if we don't have this, all posts would have extra space at the top
-    #wmd-preview > *:first-child {
-      margin-top: 0 !important;
-    }
 
-    #wmd-input, #wmd-preview-scroller, #wmd-preview {
+    #wmd-input {
       @include box-sizing(border-box);
       width: 100%;
       height: 100%;
@@ -309,22 +276,13 @@ display: none;
       background-color: $secondary;
       word-wrap: break-word;
     }
-    #wmd-input, #wmd-preview-scroller {
+    #wmd-input {
       position: absolute;
       left: 0;
       top: 0;
       font-size: 16px;
     }
-    #wmd-preview-scroller {
-      font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
-      overflow: scroll;
-      visibility: hidden;
-      .marker, .caret {
-        display: inline-block;
-        vertical-align: top;
-      }
-    }
-    .textarea-wrapper, .preview-wrapper {
+    .textarea-wrapper {
       position: relative;
       @include box-sizing(border-box);
       height: 100%;
@@ -341,10 +299,6 @@ display: none;
         right: 4px;
       }
     }
-    .preview-wrapper {
-      padding-left: 5px;
-      float: right;
-    }
   }
   #wmd-button-bar {
     display: none;