added parsedown extension for header ids (#388) (#399)

assets/sass/documentation.scss

@@ -0,0 +1,25 @@
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+.markdown-body {
+    h1, h2, h3, h4, h5, h6 {
+        a.anchor {
+            float: left;
+            font-size: 0.5em;
+            margin-left: -1em;
+            padding-top: 0.5em;
+            color: $text-color;
+            display: none;
+        }
+    }
+}
+
+@media (min-width: $screen-sm-min) {
+    .markdown-body {
+        padding-left: 25px;
+    }
+}