update packages and add valign

scripts/reveal.js/css/theme/league.scss

@@ -0,0 +1,39 @@
+/**
+ * League theme for reveal.js.
+ *
+ * This was the default theme pre-3.0.0.
+ *
+ * Copyright (C) 2011-2012 Hakim El Hattab, http://hakim.se
+ */
+
+// Load utils
+@use 'sass:color';
+@use 'template/mixins' as mixins;
+
+// Inject theme variables (with some overrides)
+@use 'template/settings' with (
+	$background: radial-gradient(rgba(85, 90, 95, 1), rgba(28, 30, 32, 1)),
+	$background-color: rgba(28, 30, 32, 1),
+	$heading-text-shadow: #{0px 0px 6px rgba(0, 0, 0, 0.2)},
+	$heading1-text-shadow: #{0 1px 0 #ccc,
+	0 2px 0 #c9c9c9,
+	0 3px 0 #bbb,
+	0 4px 0 #b9b9b9,
+	0 5px 0 #aaa,
+	0 6px 1px rgba(0, 0, 0, 0.1),
+	0 0 5px rgba(0, 0, 0, 0.1),
+	0 1px 3px rgba(0, 0, 0, 0.3),
+	0 3px 5px rgba(0, 0, 0, 0.2),
+	0 5px 10px rgba(0, 0, 0, 0.25),
+	0 20px 20px rgba(0, 0, 0, 0.15)}
+);
+
+// Inject the theme template
+@use 'template/theme';
+
+// Include theme-specific fonts
+@import url('./fonts/league-gothic/league-gothic.css');
+@import url('https://fonts.googleapis.com/css?family=Lato:400,700,400italic,700italic');
+
+// Change text colors against light slide backgrounds
+@include mixins.light-bg-text-color(#222);