Standardise on 'colour' for user-facing text

wagtail/contrib/styleguide/templates/wagtailstyleguide/base.html

@@ -20,8 +20,8 @@
         <h2>Contents</h2>
         <nav>
             <ul class="unlist">
-                <li><a href="#palette">Color palette</a></li>
-                <li><a href="#accessiblecolors">Accessible color combinations</a></li>
+                <li><a href="#palette">Colour palette</a></li>
+                <li><a href="#accessiblecolours">Accessible colour combinations</a></li>
                 <li><a href="#typography">Typography</a></li>
                 <li><a href="#help">Help text</a></li>
                 <li><a href="#listings">Listings</a></li>
@@ -41,7 +41,7 @@
         </nav>
 
         <section id="palette" class="palette">
-            <h2>Color palette</h2>
+            <h2>Colour palette</h2>
 
             <ul>
                 <li class="color-teal">color-teal</li>
@@ -68,12 +68,12 @@
             </ul>
         </section>
 
-        <section class="palette" id="accessiblecolors">
+        <section class="palette" id="accessiblecolours">
 
-        <h2>Accessible color combinations</h2>
-            <p>WCAG (Web Content Accessibility Guidelines) ensures that content is accessible by everyone, regardless of any disability or user device. To ensure text remains compliant with WCAG 2.0 AA standards, use only these permitted color combinations.</p>
+        <h2>Accessible colour combinations</h2>
+            <p>WCAG (Web Content Accessibility Guidelines) ensures that content is accessible by everyone, regardless of any disability or user device. To ensure text remains compliant with WCAG 2.0 AA standards, use only these permitted colour combinations.</p>
 
-            <p>Use this <a href="https://accessibility.oit.ncsu.edu/tools/color-contrast/accessible-color-palette.php?colors=43b1b0,358c8b,246060,71b2d4,cd3238,e9b04d,189370,f37e77,fcf2f2,ffffff,000000,333333,404040,666666,d9d9d9,e6e6e6,fafafa,cacaca&level=AA">Color Palette Accessibility Checker</a> to test new color combinations using the existing color palette.</p>
+            <p>Use this <a href="https://accessibility.oit.ncsu.edu/tools/color-contrast/accessible-color-palette.php?colors=43b1b0,358c8b,246060,71b2d4,cd3238,e9b04d,189370,f37e77,fcf2f2,ffffff,000000,333333,404040,666666,d9d9d9,e6e6e6,fafafa,cacaca&amp;level=AA">Color Palette Accessibility Checker</a> to test new colour combinations using the existing colour palette.</p>
 
             <h3>Small text combinations: for font sizes 16px or smaller</h3>
             <ul class="contrast">