diff --git a/app/main.css b/app/main.css
index 4210a27f..3d9ca5f6 100644
--- a/app/main.css
+++ b/app/main.css
@@ -105,10 +105,22 @@ details {
   overflow: hidden;
 }
 
+details > summary::-webkit-details-marker {
+  display: none;
+}
+
+details > summary > svg {
+  transition: all 0.25s cubic-bezier(0.07, 0.95, 0, 1);
+}
+
 details[open] {
   overflow-y: auto;
 }
 
+details[open] > summary > svg {
+  transform: rotate(90deg);
+}
+
 footer li:hover {
   text-decoration: underline;
 }
diff --git a/app/ui/archiveTile.js b/app/ui/archiveTile.js
index 6ef712cd..414c6722 100644
--- a/app/ui/archiveTile.js
+++ b/app/ui/archiveTile.js
@@ -126,11 +126,22 @@ function archiveDetails(translate, archive) {
         ${archive.open ? 'open' : ''}
         ontoggle="${toggled}"
       >
-        <summary class="text-blue-dark text-sm cursor-pointer"
-          >${translate('fileCount', {
-            num: archive.manifest.files.length
-          })}</summary
+        <summary
+          class="flex items-center text-blue-dark text-sm cursor-pointer outline-none"
         >
+          <svg
+            class="fill-current w-4 h-4 mr-1"
+            xmlns="http://www.w3.org/2000/svg"
+            viewBox="0 0 20 20"
+          >
+            <path
+              d="M12.95 10.707l.707-.707L8 4.343 6.586 5.757 10.828 10l-4.242 4.243L8 15.657l4.95-4.95z"
+            />
+          </svg>
+          ${translate('fileCount', {
+            num: archive.manifest.files.length
+          })}
+        </summary>
         ${list(
           archive.manifest.files.map(f => fileInfo(f)),
           'list-reset h-full'
diff --git a/assets/arrow-r.svg b/assets/arrow-r.svg
deleted file mode 100644
index a0669c3a..00000000
--- a/assets/arrow-r.svg
+++ /dev/null
@@ -1,21 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<svg width="7px" height="12px" viewBox="0 0 7 12" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
-    <!-- Generator: sketchtool 53 (72520) - https://sketchapp.com -->
-    <title>D8471D57-B56D-4AA0-B2BD-A1A6D29ABA2C</title>
-    <desc>Created with sketchtool.</desc>
-    <defs>
-        <path d="M11.983616,7.98361603 C11.9835405,7.63002294 11.8430152,7.29093967 11.5929494,7.04094936 L7.59294936,3.04094936 C7.06977751,2.53565308 6.23816966,2.54287953 5.72385793,3.05719126 C5.2095462,3.57150299 5.20231975,4.40311085 5.70761603,4.92628269 L8.76494936,7.98361603 L5.70761603,11.0409494 C5.20231975,11.5641212 5.2095462,12.3957291 5.72385793,12.9100408 C6.23816966,13.4243525 7.06977751,13.431579 7.59294936,12.9262827 L11.5929494,8.92628269 C11.8430152,8.67629239 11.9835405,8.33720911 11.983616,7.98361603 Z" id="path-1"></path>
-    </defs>
-    <g id="Page-1" stroke="none" stroke-width="1" fill="none" fill-rule="evenodd">
-        <g id="Send_Home-With-Files" transform="translate(-773.000000, -257.000000)">
-            <g id="List-Item-1" transform="translate(744.000000, 168.000000)">
-                <g id="Expand-Icon" transform="translate(24.000000, 87.000000)">
-                    <mask id="mask-2" fill="white">
-                        <use xlink:href="#path-1"></use>
-                    </mask>
-                    <use id="Shape" fill="#0060DF" fill-rule="nonzero" xlink:href="#path-1"></use>
-                </g>
-            </g>
-        </g>
-    </g>
-</svg>
\ No newline at end of file