*Toot: fix the thread line covers preview (#10)

src/timelines/RegularToot.tsx

@@ -187,7 +187,7 @@ function TootAuthorGroup(props: { status: mastodon.v1.Status; now: Date }) {
           }}
         />
         <time datetime={toot().createdAt}>
-          {formatRelative(props.now, toot().createdAt)}
+          {formatRelative(toot().createdAt, props.now)}
         </time>
         <span>
           @{toot().account.username}@{new URL(toot().account.url).hostname}

src/timelines/toot.module.css

@@ -118,6 +118,8 @@
   transition: color 220ms var(--tutu-anim-curve-std), background-color 220ms var(--tutu-anim-curve-std);
   padding-bottom: 8px;
   overflow: hidden;
+  z-index: 1;
+  position: relative;
 
   >img {
     max-width: 100%;