Add blue button

Author: mrmrs

index.html

@@ -102,7 +102,7 @@ <h1 class="f4 fw6 f1-ns lh-title measure mt0">
                 </div>
                 <div class="fl-l w-50-l tl tc-ns pt4 pt5-ns">
                   <a 
-                    class="fw6 dib ba b--black-20 bg-white-05 f5 ph4 pv3 br2 black-70 grow no-underline" 
+                    class="fw6 dib ba b--black-20 bg-blue white f5 ph4 pv3 br2 grow no-underline" 
                     href="https://raw.githubusercontent.com/tachyons-css/tachyons/master/css/tachyons.min.css">
                     Download <code class="f6 fw4 di">v4.3.1</code>
                   </a>