Add project files.

Shared/MainLayout.razor

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+@inherits LayoutComponentBase
+
+<PageTitle>LiveChat</PageTitle>
+
+<div class="page">
+    <main>
+        <div class="top-row px-4">
+            <h1>LiveChat</h1>
+            <!---<a href="https://docs.microsoft.com/aspnet/" target="_blank">About</a>-->
+        </div>
+
+        <article class="content px-4">
+            @Body
+        </article>
+    </main>
+</div>

Shared/MainLayout.razor.css

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+.page {
+    position: relative;
+    display: flex;
+    flex-direction: column;
+}
+
+main {
+    flex: 1;
+}
+
+.top-row {
+    background-color: #171717;
+    color: #f1f1f1;
+    border-bottom: 1px solid #252525;
+    justify-content: center;
+    height: 3.5rem;
+    display: flex;
+    align-items: center;
+}
+
+    .top-row ::deep a, .top-row .btn-link {
+        white-space: nowrap;
+        margin-left: 1.5rem;
+    }
+
+    .top-row a:first-child {
+        overflow: hidden;
+        text-overflow: ellipsis;
+    }
+
+@media (max-width: 640.98px) {
+    .top-row.auth {
+        justify-content: space-between;
+    }
+
+    .top-row a, .top-row .btn-link {
+        margin-left: 0;
+    }
+}
+
+@media (min-width: 641px) {
+    .page {
+        flex-direction: row;
+    }
+
+    .sidebar {
+        width: 250px;
+        height: 100vh;
+        position: sticky;
+        top: 0;
+    }
+
+    .top-row {
+        position: sticky;
+        top: 0;
+        z-index: 1;
+    }
+
+    .top-row, article {
+        padding-left: 2rem !important;
+        padding-right: 1.5rem !important;
+    }
+}

Shared/SurveyPrompt.razor

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+<div class="alert alert-secondary mt-4">
+    <span class="oi oi-pencil me-2" aria-hidden="true"></span>
+    <strong>@Title</strong>
+
+    <span class="text-nowrap">
+        Please take our
+        <a target="_blank" class="font-weight-bold link-dark" href="https://go.microsoft.com/fwlink/?linkid=2186158">brief survey</a>
+    </span>
+    and tell us what you think.
+</div>
+
+@code {
+    // Demonstrates how a parent component can supply parameters
+    [Parameter]
+    public string? Title { get; set; }
+}