New base code for mempool blockchain explorerer

frontend/src/app/components/master-page/master-page.component.ts

@@ -0,0 +1,27 @@
+import { Component, OnInit } from '@angular/core';
+import { StateService } from '../../services/state.service';
+
+@Component({
+  selector: 'app-master-page',
+  templateUrl: './master-page.component.html',
+  styleUrls: ['./master-page.component.scss']
+})
+export class MasterPageComponent implements OnInit {
+  navCollapsed = false;
+  isOffline = false;
+
+  constructor(
+    private stateService: StateService,
+  ) { }
+
+  ngOnInit() {
+    this.stateService.isOffline$
+      .subscribe((state) => {
+        this.isOffline = state;
+      });
+  }
+
+  collapse(): void {
+    this.navCollapsed = !this.navCollapsed;
+  }
+}