Change font for CS1822 slides; change character for bullet point items.

templates/impress.cs/css/cs1822.css

@@ -7,7 +7,7 @@
  */
 
 .step {
-    font-family: Sans;
+    font-family: 'Liberation Sans', Arial, sans-serif;
 }
 
 .step.concept {
@@ -45,7 +45,8 @@ ul {
 }
 
 li::before {
-    content: "○ "; 
+    /* other bullet characters: ○‣▻► */
+    content: "➢ ";
     color: #00a69e;
 }