style blog posts and grid

src/css/base.scss

@@ -28,11 +28,14 @@ body {
 }
 
 main {
-  padding: 2rem 2rem 6rem;
   background: $color-white;
   color: $color-black;
 }
 
+section {
+  padding: 2rem 2rem 6rem;
+}
+
 a {
   color: $color-link;
   transition: all .2s ease-in-out;
@@ -66,4 +69,8 @@ h3 {
 
 img {
   max-width: 100%;
+}
+
+.section-title {
+  margin-bottom: 1.6rem;
 }