diff --git a/assets/style-course.css b/assets/style-course.css
index 0a8acba..597b58c 100644
--- a/assets/style-course.css
+++ b/assets/style-course.css
@@ -286,6 +286,13 @@ span.formula {
     margin-top: 4ex;
     margin-bottom: 4ex;
   }
+
+  figure img {
+    min-width: min(100%, 800px);
+    max-width: min(100%, 800px);
+    max-height: 50vh;
+    object-fit: contain;
+  }
 }
 
 .course .margin em {
@@ -294,14 +301,6 @@ span.formula {
   color: #2aa6da;
 }
 
-.course .tip p,
-.course .unit p,
-.course .indepth p,
-.course .attention p,
-.course .danger p {
-  margin-block-end: 0;
-}
-
 .course .margin.tip:before,
 .course .margin.unit:before,
 .course .margin.indepth:before,
diff --git a/assets/style-slide.css b/assets/style-slide.css
index 1b3c8e7..25a43ae 100644
--- a/assets/style-slide.css
+++ b/assets/style-slide.css
@@ -176,11 +176,11 @@ section.has-dark-background h6 {
 }
 
 .reveal ul {
-    list-style-type: disc;
+    list-style-type: square;
 }
 
 .reveal ul ul {
-    list-style-type: square;
+    list-style-type: "- ";
 }
 
 .reveal ul ul ul {
@@ -195,6 +195,10 @@ section.has-dark-background h6 {
     margin-left: 40px;
 }
 
+.reveal ul li::marker {
+  color: #2aa6da;
+}
+
 .reveal dt {
     font-weight: bold;
 }
diff --git a/templates/html/page.html b/templates/html/page.html
index fc4cac9..41982a1 100644
--- a/templates/html/page.html
+++ b/templates/html/page.html
@@ -26,7 +26,7 @@
       }
       function highlightRef(ref) {
         console.log(ref)
-        document.getElementById('ref_' + ref).style.background='red';
+        document.getElementById('ref_' + ref).style.background='#2aa6da';
         setTimeout(() => {
           document.getElementById('ref_' + ref).style.background='none';
         }, 500);