fix: improve the style of <summary>

- Add Safari `summary::marker` compatibility code.
- Vertical centered.

Author: YDX-2147483647

src/util.css

@@ -56,6 +56,7 @@ details.now-fixed {
   > summary {
     cursor: pointer;
     margin-left: -0.5em;
+    margin-bottom: 0.25em;
 
     display: grid;
     grid-template-columns: auto 1fr;
@@ -66,15 +67,19 @@ details.now-fixed {
 
     /* Replace ::marker with ::before */
     list-style: none;
+    &::-webkit-details-marker {
+      display: none;
+    }
 
     &::before {
-      display: block;
+      display: flex;
+      align-items: center;
       height: 2em;
       width: 2em;
     }
 
     > p {
-      margin-top: 0;
+      margin-block: 0;
     }
   }