Add logo to tx tracker page, fix bugs

frontend/src/app/components/tracker/tracker.component.scss

@@ -8,6 +8,7 @@
 .mobile-container {
   width: 100vw;
   height: 100vh;
+  height: 100svh;
   max-width: 600px;
   max-height: 1000px;
   box-sizing: border-box;
@@ -21,6 +22,29 @@
   }
 }
 
+.heading {
+  display: flex;
+  flex-direction: row;
+  justify-content: space-between;
+  align-items: flex-start;
+
+  & > * {
+    flex-basis: 0;
+    flex-grow: 1;
+  }
+
+  .heading-label {
+    text-align: center;
+    margin: 0 1em;
+  }
+}
+
+.nav-header {
+  position: relative;
+  box-shadow: 0 -5px 15px #000;
+  z-index: 100;
+}
+
 .blockchain-wrapper {
   position: relative;
   display: flex;