add css, next post feature

change favicon, add more readme, add extra example post, dark/light mode toggle

static/styles/index.css

@@ -0,0 +1,16 @@
+h2 {
+  display: inline-block;
+}
+
+#fancy-title:checked ~ h2 {
+  color: white;
+  padding-right: 0px 4px;
+  background-color: dodgerblue;
+  text-shadow: 1px 1px 1px gray, 4px 4px 1px blue;
+}
+
+#checkboxes {
+  position: relative;
+  top: 0;
+  left: 0;
+}