add new black theme

css/theme/source/black.scss

@@ -0,0 +1,35 @@
+/**
+ * Black theme for reveal.js.
+ *
+ * Copyright (C) 2014 Hakim El Hattab, http://hakim.se
+ */
+
+
+// Default mixins and settings -----------------
+@import "../template/mixins";
+@import "../template/settings";
+// ---------------------------------------------
+
+
+// Include theme-specific fonts
+@import url(https://fonts.googleapis.com/css?family=Montserrat:700);
+@import url(https://fonts.googleapis.com/css?family=Open+Sans:400,700,400italic,700italic);
+
+
+// Override theme settings (see ../template/settings.scss)
+$backgroundColor: #111;
+
+$mainFont: 'Open Sans', Helvetica, sans-serif;
+$mainFontSize: 32px;
+$headingFont: 'Montserrat', Helvetica, sans-serif;
+$headingTextShadow: none;
+$headingLetterSpacing: normal;
+$headingTextTransform: none;
+$linkColor: #3992fb;
+$linkColorHover: lighten( $linkColor, 15% );
+$selectionBackgroundColor: lighten( $linkColor, 25% );
+
+
+// Theme template ------------------------------
+@import "../template/theme";
+// ---------------------------------------------