feat: app icon button round

config/assets.php

@@ -20,6 +20,7 @@ return [
             ],
             'default' => [
                 'css/vendor-overrides/multi-select.css',
+                'css/components/app-icon-button.css',
                 'css/components/app-buttons.css',
                 'css/vendor-overrides/gridjs.css',
                 'css/layout/app-topbar.css',

pages/admin/mail-log/view(default).phtml

@@ -23,7 +23,7 @@ $statusBadge = $status->badgeVariant();
     ?>
     <div class="app-details-titlebar">
       <h1>
-        <a href="admin/mail-log" title="<?php e(t('Back')); ?>"><i class="bi bi-arrow-left"></i></a>
+        <a href="admin/mail-log" title="<?php e(t('Back')); ?>" class="app-icon-button"><i class="bi bi-arrow-left"></i></a>
         <?php e(t('View mail log')); ?>
       </h1>
     </div>

templates/partials/app-details-titlebar.phtml

@@ -70,7 +70,7 @@ $resolveToneClass = static function (string $tone, string $detailActionKind, str
 >
   <h1>
     <?php if ($backHref !== ''): ?>
-      <a href="<?php e($backHref); ?>" title="<?php e($backTitle); ?>"><i class="bi bi-arrow-left"></i></a>
+      <a href="<?php e($backHref); ?>" title="<?php e($backTitle); ?>" class="app-icon-button"><i class="bi bi-arrow-left"></i></a>
     <?php endif; ?>
     <?php e($title); ?>
   </h1>

web/css/components/app-details-titlebar.css

@@ -43,22 +43,7 @@
     white-space: nowrap;
   }
 
-  .app-details-titlebar h1 i {
-    background: var(--app-background-color);
-    width: 35px;
-    height: 29px;
-    font-size: 15px; /* icon-font metric — intentional px */
-    border-radius: var(--app-border-radius);
-    display: inline-flex;
-    align-items: center;
-    justify-content: center;
-    color: var(--app-contrast);
-    border: 1px solid var(--app-border);
-    color: var(--app-muted-color);
-    box-shadow: rgba(0, 0, 0, 0.1) 0px 1px 2px;
-  }
-
-  .app-details-titlebar h1:has(i) {
+  .app-details-titlebar h1:has(.app-icon-button) {
     display: flex;
     align-items: center;
     gap: 7px;

web/css/components/app-icon-button.css

@@ -0,0 +1,34 @@
+@layer components {
+  /* Reusable round ghost icon button — transparent circle with subtle hover.
+     Used for back buttons, inline icon actions, etc. */
+  .app-icon-button {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    width: 28px;
+    height: 28px;
+    padding: 0;
+    border: none;
+    border-radius: 50%;
+    background: transparent;
+    color: var(--app-muted-color);
+    font-size: var(--text-sm);
+    line-height: 1;
+    cursor: pointer;
+    text-decoration: none;
+    transition:
+      background-color var(--app-transition),
+      color var(--app-transition);
+  }
+
+  .app-icon-button:hover,
+  .app-icon-button:focus-visible {
+    background: color-mix(in srgb, var(--app-contrast) 8%, transparent);
+    color: var(--app-contrast);
+  }
+
+  .app-icon-button i {
+    font-size: 15px; /* icon-font metric — intentional px */
+    line-height: 1;
+  }
+}