шаг 1 сделан

public/assets/css/app.css

@@ -0,0 +1,53 @@
+* {
+    box-sizing: border-box;
+}
+
+body {
+    margin: 0;
+    min-height: 100vh;
+    font-family: Arial, sans-serif;
+    color: #18201b;
+    background: #f7f8f4;
+}
+
+.page {
+    min-height: 100vh;
+    display: grid;
+    place-items: center;
+    padding: 24px;
+}
+
+.start-screen {
+    width: min(760px, 100%);
+    padding: 32px;
+    border: 1px solid #d9dfd3;
+    border-radius: 8px;
+    background: #ffffff;
+}
+
+.eyebrow {
+    margin: 0 0 8px;
+    font-size: 14px;
+    color: #687466;
+}
+
+h1 {
+    margin: 0 0 16px;
+    font-size: 40px;
+    line-height: 1.1;
+}
+
+p {
+    font-size: 18px;
+    line-height: 1.55;
+}
+
+.status-box {
+    display: flex;
+    gap: 8px;
+    align-items: center;
+    margin-top: 24px;
+    padding: 14px 16px;
+    border-radius: 8px;
+    background: #eef4ea;
+}

public/index.php

@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Core\Database;
+
+require_once dirname(__DIR__) . '/app/bootstrap.php';
+
+$dbStatus = 'not_checked';
+
+try {
+    Database::pdo()->query('SELECT 1');
+    $dbStatus = 'connected';
+} catch (Throwable $exception) {
+    $dbStatus = app_env('APP_DEBUG', 'false') === 'true'
+        ? 'error: ' . $exception->getMessage()
+        : 'error';
+}
+
+view('pages/home', [
+    'title' => 'Рыбсток',
+    'dbStatus' => $dbStatus,
+]);