Which AI Can Create the Coolest Web Page? GPT 5.2 vs Gemini 3.0 Pro vs Opus 4.5 vs bolt.new vs v0 vs Lovable

Source: Dev.to

Introduction

As the first step in my smartphone app development journey, I am developing “Sumineko”, a very simple smartphone app that lets you watch random cat videos endlessly in the corner of your screen while multitasking.

To register this app on official stores, I need to prepare a privacy policy page on the web, so I decided to take this opportunity to create a Landing Page (LP) for the app.

Therefore, in this article, I will have representative LLMs and AI coding services create the foundation of the LP, and I will compare their results based on my own prejudice and bias.

Contenders

Note on Treating Them as Equals
Pure LLMs (Gemini 3.0 Pro, Opus 4.5, GPT 5.2) and development support systems with built‑in LLMs (bolt.new, v0, Lovable) have different system architectures. For convenience, I treat them as equals to subjectively compare the quality of web page generation results using the same prompt. This experiment lacks strict rigor.

Prompts

I prepared two patterns to loosely verify their ability to ad‑lib and their faithful adherence to requirements.

Minimal Pattern

A pattern where I primarily provide a simple overview of “Sumineko” and the necessary sections, leaving the design and wording up to the AI.

# Landing Page Creation for "Sumineko" (Corner Cat)

## Request
Design and implement a landing page (Top page only) for the smartphone app "Sumineko".
**You have full creative freedom** regarding the layout, color palette, typography, and copywriting. Please build what you consider to be the **most attractive and modern** design for this product.

## Product Concept
- **App Name**: Sumineko (Corner Cat)
- **Core Value**: A "healing" app that lets users watch cat videos in a Picture-in-Picture (PiP) window while multitasking on their phone.
- **Vibe**: Relaxing, Minimal, Cute but sophisticated.

## Technical Stack
- Next.js 15 (App Router)
- Tailwind CSS
- TypeScript
- Lucide React (for icons)

## Essential Sections (Skeleton)
Please include the following three sections. The order and presentation are up to you.

### 1. Hero Section
- Create a catchy headline and sub‑headline that conveys the app's appeal.
- Include "App Store" and "Google Play" buttons (UI only).
- Use a placeholder or CSS art for the main visual.

### 2. Experience / Demo Section (Critical Logic)
This section must adapt based on the user's device:
- **On Desktop (PC)**: Display a mock "Video Player" and a "Start Picture-in-Picture" button to let users simulate the experience in the browser.
- **On Mobile**: Display a message like "Experience the demo on PC" and guide them to the App Store buttons instead.

### 3. Collection Section
- Introduce the feature where users can "collect" the cats they have watched.
- Visualize this "collection" aspect (e.g., a grid of cat placeholders, a list, etc.).

## Assets & Copy
- **No assets provided**: Use placeholders (e.g., `via.placeholder.com` or CSS shapes) for all images and videos.
- **Copywriting**: Please write engaging English copy for headings and descriptions based on the product concept.

## Goal
Surprise me with a high‑quality, polished UI that balances "Healing/Cute" with "Modern Web Design."

Detailed Instruction Pattern

A micromanagement pattern that, in addition to the overview and necessary sections, gives detailed instructions on the structure of each section, wording, and design aspects like color schemes.

# Landing Page Creation for "Sumineko" (Corner Cat)

## Project Overview
Create a landing page (Top page only) for the smartphone app "Sumineko" (Corner Cat), which allows users to watch cat videos in Picture-in-Picture (PiP) mode while multitasking. The PC browser version offers a free trial, while the smartphone version is a paid app.

## Assets
- **No assets are provided in advance.**
- Please use **placeholders** (e.g., solid colors, CSS patterns, or placeholder image services like `via.placeholder.com`) for all images, icons, and videos.
- Assume the file paths for images will be logically placed in `/public/images/` for future replacement, but use placeholders for now.

## Technical Requirements
- **Framework**: Next.js 15 (App Router)
- **Styling**: TailwindCSS
- **Language**: TypeScript
- **Deployment**: Targeted for Cloudflare Pages
- **i18n**: Foundation for multi‑language support required (manage text in JSON files).
  - Create the **English** version as the default.
- **Code Quality**: Ensure components are modular and reusable. Avoid monolithic files.
- **Images**: Use standard Image component or Next.js Image with placeholder sources.
- **Videos**: Lazy loading implementation (Intersection Observer).
- **Fonts**: System fonts or optimized fonts (e.g., Inter or a rounded font for a soft look).

## Environment Variables
Assume the following environment variables are used:
- `NEXT_PUBLIC_STORE_MODE` – Values: `coming-soon` or `live`
- `NEXT_PUBLIC_APP_STORE_URL` – URL for App Store
- `NEXT_PUBLIC_GOOGLE_PLAY_URL` – URL for Google Play

## Color Palette
- **Background**: #FAF8F5 (Warm off‑white)
- **Main Text**: #8B7355 (Brownish)
- **Accent**: Add a soft, harmonious color if necessary.

## Design Guidelines
- Minimal and clean.
- Focus on "what we want to show the user" in each section.
- A soft, healing atmosphere suitable for a cat app.
- No header required.

---

## Page Structure

### 1. Top Page (`/`)

#### Section 1: Hero

**Layout**: 2 columns (Text on Left, Video on Right).

**Left Side**
- **Mascot Image**: Use a placeholder.
- **Catchphrase**: "Cats in the Corner of Your Screen."
- **Sub‑copy**: "Just open and play. Infinite cat videos for your multitasking moments."
- **3 Selling Points (Use icons for visual appeal)**
  1. **Instant Comfort** – One tap to play. No searching, no choosing.
  2. **Heal Your Mind** – Perfect for when you feel tired, stressed, or lonely.
  3. **Stay Focused** – Unintrusive PiP window. Work and study with cats by your side.
- **Store Buttons**
  - If `NEXT_PUBLIC_STORE_MODE` is `coming-soon` → Show "Coming Soon" label.
  - If `NEXT_PUBLIC_STORE_MODE` is `live` → Show Store Links.
- **Supplementary Text**: "One‑time purchase. Yours forever."

**Right Side**
- **Demo Video Frame**
  - Placeholder for WebM video (muted, loop, auto‑play).
  - Ensure a poster image (thumbnail) can be set.

#### Section 2: Experience Section

**PC View**
- **Heading**: "Try Sumineko in Your Browser"
- **Description**: "Click the button below to start the Picture‑in‑Picture player. Enjoy the cats while you work on other tasks."
- **Video Player Frame**: Placeholder (logic implementation not required yet).
- **"Start PiP" Button**: UI only (functionality to be implemented later).

**Mobile View**
- **Heading**: "Try the Web Demo on Desktop"
- **Description**: "Open this page on your computer to experience the full demo."