Adding lightable theme
diff --git a/inst/NEWS.md b/inst/NEWS.md
index 6235eb8..b7de0c8 100644
--- a/inst/NEWS.md
+++ b/inst/NEWS.md
@@ -28,10 +28,14 @@
 
 * Fixed a bug when using UTF-8 on non-UTF-8 system. (#440, thanks @jokorn)
 
+* Added a global option to control whether to preview HTML tables in RStudio 
+viewer. If you want to disable the default behavior, try to set 
+`options(kableExtra_view_html = F)`. (#455)
 
 
-kableExtra ]
-1.1.0
+
+
+kableExtra 1.1.0
 --------------------------------------------------------------------------------
 
 # Major Changes
diff --git a/inst/lightable-0.0.1/lightable.css b/inst/lightable-0.0.1/lightable.css
new file mode 100644
index 0000000..4c45eb2
--- /dev/null
+++ b/inst/lightable-0.0.1/lightable.css
@@ -0,0 +1,81 @@
+/*!
+ * lightable v0.0.1
+ * Copyright 2020 Hao Zhu
+ * Licensed under MIT (https://github.com/haozhu233/kableExtra/blob/master/LICENSE)
+ */
+
+.lightable-minimal {
+  border-collapse: separate;
+  border-spacing: 16px 1px;
+  width: 100%;
+}
+
+.lightable-minimal thead tr th {
+  border-bottom: 2px solid black;
+  empty-cells: hide;
+}
+
+.lightable-minimal tbody tr:first-child td {
+  padding-top: 0.5em;
+}
+
+.lightable-minimal.lightable-hover tr:hover {
+  background-color: #f5f5f5;
+}
+
+.lightable-minimal.lightable-striped tr:nth-child(even) {
+  background-color: #f5f5f5;
+}
+
+.lightable-classic {
+  border-top: 2px solid #111111;
+  border-bottom: 2px solid #111111;
+  width: 100%;
+}
+
+.lightable-classic thead tr:last-child th {
+  border-bottom: 1px solid #111111;
+}
+
+.lightable-classic.lightable-hover tr:hover {
+  background-color: #f5f5f5;
+}
+
+.lightable-classic.lightable-striped tr:nth-child(even) {
+  background-color: #f5f5f5;
+}
+
+.lightable-material {
+  min-width: 100%;
+  white-space: nowrap;
+  table-layout: fixed;
+  font-family: Roboto, sans-serif;
+  border: 1px solid #EEE;
+  border-collapse: collapse;
+}
+
+.lightable-material th {
+  padding: 0.8em;
+  background-color: #f5f5f5;
+}
+
+.lightable-material td {
+  padding: 0.8em;
+  border-top: 1px solid #eeeeee;
+}
+
+.lightable-material.lightable-hover tr:hover {
+  background-color: #f5f5f5;
+}
+
+.lightable-material.lightable-striped tr:nth-child(even) {
+  background-color: #f5f5f5;
+}
+
+.lightable-material.lightable-striped td {
+  border: 0px;
+}
+
+.lightable-material.lightable-striped thead tr:last-child th {
+  border-bottom: 1px solid #ddd;
+}