Docs: Correct tiny typos (content-collapsible.html)

Author: MauriceG

docs/content/content-collapsible.html

@@ -119,7 +119,7 @@ <h3>I'm a header</h3>
 	<h2>Theming collapsible content</h2>
 
 
-		<p>Collapsible content is minimally styled &mdash; we add only a bit of margin between the bar and content, and the header adopts the default Theme styles of the container it sits within.</p>
+		<p>Collapsible content is minimally styled &mdash; we add only a bit of margin between the bar and content, and the header adopts the default theme styles of the container it sits within.</p>
 
 		<p>To provide a stronger visual connection between the collapsible header and content, add the <code>data-content-theme</code> attribute to the wrapper and specify a theme swatch letter. This will apply the swatch's border and <em>flat</em> background color (not the gradient) to the content block and changes the corner rounding to square off the bottom of the header and round the bottom of the content block instead to visually group these elements.</p>
 
@@ -213,7 +213,7 @@ <h3>Section 4: Collapsed list</h3>
 
 
 		<h2>Collapsible sets (accordions)</h2>
-		<p>It's possible to combine multiple collapsibles into a grouped sets that acts like an <a href="content-collapsible-set.html">accordion widget</a>.</p>
+		<p>It's possible to combine multiple collapsibles into a grouped set that acts like an <a href="content-collapsible-set.html">accordion widget</a>.</p>
 
 
 	</div><!--/content-primary -->