Fix title styles.

frontend/src/app/components/mempool-block/mempool-block.component.html

@@ -1,7 +1,7 @@
 <div class="container-xl" *ngIf="mempoolBlock$ | async as mempoolBlock">
 
   <div class="title-block">
-    <h1 class="float-left">{{ ordinal$ | async }}</h1>
+    <h1>{{ ordinal$ | async }}</h1>
     <button [routerLink]="['/' | relativeUrl]" class="btn btn-sm float-right">&#10005;</button>
   </div>
 

frontend/src/app/components/mempool-block/mempool-block.component.scss

@@ -24,9 +24,9 @@
 h1 {
   margin: 0px;
   padding: 0px;
+  line-height: 1;
   @media (min-width: 576px) {
     float: left;
-    margin-right: 10px;
   }
 }