Make empty cells have height via CSS

So we do not have to add something like   in the output.

Signed-off-by: Jack Cherng <[email protected]>

Author: jfcherng

example/diff-table.css

@@ -25,6 +25,11 @@
   padding: 1px 2px;
   background: #fff;
 }
+.diff-wrapper.diff td:empty:after,
+.diff-wrapper.diff th:empty:after {
+  content: " ";
+  visibility: hidden;
+}
 .diff-wrapper.diff td a,
 .diff-wrapper.diff th a {
   color: #000;

example/diff-table.scss

@@ -52,6 +52,12 @@
     padding: 1px 2px;
     background: $bg-color;
 
+    // make empty cell has height
+    &:empty:after {
+      content: ' ';
+      visibility: hidden;
+    }
+
     a {
       color: #000;
       cursor: inherit;