index: add some lead-out text

Author: tmcdonell

index.html

@@ -56,7 +56,7 @@ <h1 style="font-family: 'Raleway'; font-weight: 800; text-shadow: 2px 2px 4px #a
         <!-- bootstrap's grid system allows up to 12 columns -->
         <div class="col-md-1"></div>
         <div class="col-md-10">
-          <p class="lead">
+          <p class="lead text-center">
             <i>Accelerate</i> is a free, general-purpose, open-source library that
             simplifies the process of developing software that targets massively
             parallel architectures including multicore CPUs and GPUs.
@@ -139,6 +139,17 @@ <h2 class="featurette-heading">
 
       <hr class="featurette-divider">
       <div class="row featurette text-center">
+        <div class="col-md-1"></div>
+        <div class="col-md-10">
+          <p class="lead">
+            The core philosophy of Accelerate is to combine <i>performance</i>,
+            <i>productivity</i>, and <i>portability</i> into a single language
+            and compiler: quickly write the compute-intensive part of your
+            program in a high-level style and leave Accelerate to work on the
+            details of code transformation for the target architecture.
+          </p>
+        </div>
+        <div class="col-md-1"></div>
         <a href="get-started.html" class="btn btn-lg btn-success" style="padding: 20px; color: white;">
           <span style="font-size:2.2em;">
             Get Started