--- a/devtools/client/themes/animation.css
+++ b/devtools/client/themes/animation.css
@@ -14,16 +14,28 @@
 :root.theme-dark {
   --animation-even-background-color: rgba(255, 255, 255, 0.05);
 }
 
 :root.theme-firebug {
   --command-pick-image: url(chrome://devtools/skin/images/firebug/command-pick.svg);
 }
 
+/* Root element of animation inspector */
+#animation-container {
+  height: 100%;
+}
+
+/* Animation List Container */
+.animation-list-container {
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+}
+
 /* Animation List Header */
 .animation-list-header {
   display: flex;
   justify-content: flex-end;
   padding: 0;
 }
 
 /* Animation Timeline Tick List */
@@ -36,18 +48,20 @@
 .animation-timeline-tick-item {
   border-left: 0.5px solid rgba(128, 136, 144, .5);
   height: 100vh;
   position: absolute;
 }
 
 /* Animation List */
 .animation-list {
+  flex: 1;
   list-style-type: none;
   margin-top: 0;
+  overflow: auto;
   padding: 0;
 }
 
 /* Animation Item */
 .animation-item {
   display: flex;
   height: 30px;
 }