split styles to accomodate themes; added light/dark theme

less/update/sw5e-light.less

@@ -0,0 +1,44 @@
+@import "_variables.less";
+@import "_variables-light.less";
+
+body.light-theme {
+  .app {
+    background: @primaryBackground;
+  }
+  h1,
+  h2,
+  h3,
+  h4,
+  h5,
+  h6 {
+    color: @headingColor;
+  }
+  h3 {
+    border-bottom: 2px solid @headerBorderColor;
+  }
+
+  a {
+    color: @linkColor;
+    text-decoration: none;
+
+    &:hover,
+    &:active {
+      text-shadow: none;
+      text-decoration: underline;
+    }
+  }
+
+  blockquote {
+    padding: 4px 8px;
+    background-color: @blockquoteBackground;
+    border: 1px solid @blockquoteBorder;
+    box-shadow: @blockquoteShadow;
+  }
+
+  hr {
+    border-width: 0 0 1px 0;
+    border-bottom: 1px solid @hrColor;
+  }
+  @import "components/forms-themes.less";
+  @import "components/sidebar-themes.less";
+}