accessibility updates

- close btn contrast ratio
- adding aria-label to carousel

web/themes/asc_bootstrap/assets/sass/layout/_default.scss

@@ -274,3 +274,9 @@ figcaption {
   padding-left: 15px;
   padding-right: 15px;
 }
+
+.close {
+    color: #000;
+    opacity: 0.8;
+    filter: alpha(opacity=80);
+}

web/themes/asc_bootstrap/css/style.css

@@ -6053,6 +6053,11 @@ figcaption {
   padding-left: 15px;
   padding-right: 15px; }
 
+.close {
+  color: #000;
+  opacity: 0.8;
+  filter: alpha(opacity=80); }
+
 .footer {
   background: #3F4443;
   border-top: none;

web/themes/asc_bootstrap/templates/field/field--field-slides2.html.twig

@@ -36,7 +36,7 @@
  * @see template_preprocess_field()
  */
 #}
-<div id="carousel" class="carousel slide" data-ride="false" data-interval="0" style="width: 100%" aria-roledescription="carousel" role="group">
+<div id="carousel" class="carousel slide" data-ride="false" data-interval="0" style="width: 100%" aria-roledescription="carousel" aria-label="OSU slideshow" role="group">
   <!-- Indicators -->
 {% if items|length > 1 %}
   <ol class="carousel-indicators">