Another attempt at fixing the background clipping

src/styles/_app_base.sass

@@ -9,7 +9,7 @@ body
 #app-main
 	display: flex
 	align-items: stretch
-	height: 100%
+	position: relative
 
 #col_sidebar
 	width: $sidebar-width
@@ -20,16 +20,17 @@ body
 	flex-direction: column
 	position: relative
 	flex: 0 0 auto
-	height: 100%
 	min-width: 150px
+	height: 100%
+	min-height: 100%
+	position: relative
 
 #col_main
-	background-color: white
-	border-right: thin solid $color-background-dark
 	width: 50% // gets overriden by JS, dragging the col-splitter
 
 #col_right
 	flex: 1 1 auto
+	padding-left: 8px // to compensate width of the splitter, which is positioned 'fixed'
 
 .col_header
 	position: relative
@@ -62,7 +63,9 @@ body
 	background-color: $color-background
 	min-height: 200px
 	cursor: col-resize
-	position: relative
+	position: fixed
+	top: 0
+	bottom: 0
 	z-index: 1
 
 .flyout.notifications

src/styles/_shots.sass

@@ -159,6 +159,7 @@
 		height: 100%
 		color: rgba($color-text-dark-hint, .5)
 		cursor: default
+		padding: 15px 10px
 		font:
 			size: 2em
 			weight: 100