Tweaking styling in preparation for writing documentation

src/changelog.html

@@ -1,4 +1,4 @@
-<div class="changelog">
+<div class="copy changelog">
   <dl>
     <dt>Pending release</dt>
     <dd>Freshened up design</dd>

src/documentation.html

@@ -1 +1,3 @@
+<div class="copy documentation">
 TODO: Write documentation
+</div>

src/sass/main.scss

@@ -101,10 +101,12 @@ header {
   }
 }
 
-.changelog {
+.copy {
   background-color: $tan;
   padding: rhythm(1/2);
+}
 
+.changelog {
   dt {
     font-weight: bold;
   }