minor #432 Design tweaks for small screens (javiereguiluz)

This PR was merged into the master branch.

Discussion
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Design tweaks for small screens

A typical problem I see with lots of Bootstrap-based templates is that they look awful in a very specific range of page widths. When the browser window is not too small and not too big, the template constraints the container width too much. This PR tries to fix this.

| Before | After
| --- | ---
| ![before_container](https://cloud.githubusercontent.com/assets/73419/21886280/5ec58cfa-d8bb-11e6-9b00-fb72cfa30ce4.png) | ![after_container](https://cloud.githubusercontent.com/assets/73419/21886283/5ff8869a-d8bb-11e6-80e4-20c87b9fd059.png)

Commits
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85c58b0 Design tweaks for small screens

Author: javiereguiluz

web/css/main.css

@@ -244,3 +244,9 @@ body#admin_post_index .item-actions {
 body#admin_post_index .item-actions a.btn + a.btn {
     margin-left: 4px
 }
+
+@media (min-width: 768px) and (max-width: 1200px) {
+    .container {
+        width: 98%;
+    }
+}