Add variable for border-radius

Signed-off-by: Jan-Christoph Borchardt <hey@jancborchardt.net>

apps/comments/css/autocomplete.scss

 	background: $color-main-background;
 	color: $color-main-text;
 	border: 1px solid $color-border;
-	border-radius: 3px;
+	border-radius: $border-radius;
 	box-shadow: 0 0 5px $color-box-shadow;
 	min-width: 120px;
 	z-index: 11110 !important;

apps/files/css/files.scss

 
 	.quota-container {
 		height: 5px;
-		border-radius: 3px;
+		border-radius: $border-radius;
 
 		div {
 			height: 100%;

core/css/apps.scss

 	padding: 4px 10px;
 	border: 1px solid #ccc;
 	box-shadow: 0 1px 0 rgba(0, 0, 0, .2);
-	border-radius: 3px;
+	border-radius: $border-radius;
 	display: inline-block;
 	white-space: nowrap;
 }
 	position: absolute;
 	background-color: $color-main-background;
 	color: $color-main-text;
-	border-radius: 3px;
+	border-radius: $border-radius;
 	z-index: 110;
 	margin: 5px;
 	margin-top: -5px;

core/css/header.scss

 		background-color: rgba($color-main-background, .97);
 		white-space: nowrap;
 		border: none;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		border-top-left-radius: 0;
 		border-top-right-radius: 0;
 		margin-top: 0;

core/css/inputs.scss

 	color: nc-lighten($color-main-text, 33%);
 	border: 1px solid nc-darken($color-main-background, 14%);
 	outline: none;
-	border-radius: 3px;
+	border-radius: $border-radius;
 	cursor: text;
 	&:not(:disabled):not(.primary) {
 		&:hover,
 		background: $color-main-background;
 		color: nc-lighten($color-main-text, 33%);
 		box-sizing: content-box;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		border: 1px solid nc-darken($color-main-background, 14%);
 		margin: 0;
 		padding: 2px 0;
 		background: $color-main-background;
 		color: nc-lighten($color-main-text, 33%);
 		box-sizing: content-box;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		border: 1px solid nc-darken($color-main-background, 14%);
 		margin: 0;
 		padding: 2px 0;
 	padding: 0;
 	border: 0 none;
 	background-color: nc-darken($color-main-background, 10%);
-	border-radius: 3px;
+	border-radius: $border-radius;
 	flex-basis: 100%;
 	height: 5px;
 	overflow: hidden;
 		background: transparent;
 	}
 	&::-moz-progress-bar {
-		border-radius: 3px;
+		border-radius: $border-radius;
 		background: $color-primary;
 		transition: 250ms all ease-in-out;
 	}
 	&::-webkit-progress-value {
-		border-radius: 3px;
+		border-radius: $border-radius;
 		background: $color-primary;
 		transition: 250ms all ease-in-out;
 	}

core/css/jquery.ocdialog.scss

 .oc-dialog {
 	background: $color-main-background;
 	color: nc-darken($color-main-text, 20%);
-	border-radius: 3px;
+	border-radius: $border-radius;
 	box-shadow: 0 0 7px $color-box-shadow;
 	padding: 15px;
 	z-index: 10000;

core/css/styles.scss

 
 ::-webkit-scrollbar-thumb {
 	background: nc-darken($color-main-background, 14%);
-	border-radius: 3px;
+	border-radius: $border-radius;
 }
 
 /* Searchbox */
 		background: transparent url('../img/actions/search-white.svg?v=1') no-repeat 6px center;
 		color: $color-primary-text;
 		border: 0;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		margin-top: 3px;
 		width: 0;
 		cursor: pointer;
 		background-color: rgba($color-main-text, 0.3);
 		color: $color-primary-text;
 		text-align: left;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		cursor: default;
 	}
 	.update {
 	margin-top: 8px;
 	padding: 5px;
 	background: rgba($color-error, .15);
-	border-radius: 3px;
+	border-radius: $border-radius;
 }
 
 .warning {
 	margin-top: 10px;
 	padding: 4px 8px;
 	width: auto;
-	border-radius: 3px;
+	border-radius: $border-radius;
 	border: none;
 
 	.ui-state-default,

core/css/tooltip.scss

 	color: $color-main-text;
 	box-shadow: 0 1px 10px $color-box-shadow;
 	text-align: center;
-	border-radius: 3px;
+	border-radius: $border-radius;
 }
 
 .tooltip-arrow {

core/css/variables.scss

 $color-loading-dark: #bbbbbb;
 $color-box-shadow: rgba(nc-darken($color-main-background, 30%), 0.75);
 $color-border: nc-darken($color-main-background, 8%);
+$border-radius: 3px;

settings/css/settings.scss

 		transform: translate(-50%, -50%);
 		background: #fff;
 		color: #333;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		box-shadow: 0 0 7px #888;
 		padding: 15px;
 		.jcrop-holder {
 		color: #555;
 		background-color: transparent;
 		border: 1px solid #555;
-		border-radius: 3px;
+		border-radius: $border-radius;
 		padding: 3px 6px;
 	}
 	a {
 span {
 	&.success {
 		background: #37ce02;
-		border-radius: 3px;
+		border-radius: $border-radius;
 	}
 	&.error {
 		background: #ce3702;