**Developing the Web App**

I'm currently focused on the `index.html` structure. My priority is to initialize the 3D scene with Three.js. Right now, I'm setting up the basic scene, camera, and renderer. Next, I plan to create a rudimentary Rubik's Cube object with the interactive face rotations. I aim to achieve the clickable rotations through event listeners.

**Inspecting Three.js**

I've confirmed `three.min.js`'s presence and size. Currently, I'm examining its components: core, loaders, cameras, lights, geometries, materials, and renderers. My next move is to determine if OrbitControls is included or, alternatively, to create a streamlined implementation for optimal control. I'm leaning toward a clean custom solution.


**Confirming Orbit Control**

I've determined that `three.min.js` doesn't include `OrbitControls`, which is located in `examples`. Therefore, I'll be creating a custom camera orbit control, including click-and-drag rotation and pinch-to-zoom, as well as raycasting for Rubik's Cube interaction. I'm focusing on simplicity and reliability. My next plan is designing the Rubik's Cube app in `index.html`.
I'm envisioning a dark-themed UI with a floating overlay, adopting a modern, clean style akin to Tailwind and using vanilla CSS. I'll include a "Scramble" button for randomized moves and a "Reset/Solve" option.


**Adding UI Elements**

Now, I'm integrating UI elements. I'm adding a speed slider for animations, a move counter, and a stopwatch timer. I also plan an interactive guide to demonstrate camera orbit and face rotation. I'm focusing on user-friendliness.

**Cubelet and Color Scheme**

I'm now focusing on the Rubik's Cube structure and color scheme. I've confirmed 26 visible cubies (or 27, but center core can be hidden) and the standard color scheme for faces: Green, Blue, White, Yellow, Red, and Orange. I'm making sure to use the correct hex codes for each color. Unseen parts will be black or dark grey.

**Implementing Interactivity**

I'm developing the interactivity. Left-click dragging on the background will orbit the camera. When a user clicks a cube face or cubelet, it initiates a rotation.


**Designing Rotation Control**

I'm now prioritizing the rotation controls. I've decided on on-screen move buttons (U, D, L, R, F, B, and their inverses) and click-and-drag slice rotation. Camera orbit will be by dragging the background or using a dedicated right-click (or dedicated toggle) for camera orbit mode. This approach is more intuitive and robust, so I can provide a seamless experience for both touch and mouse interactions. I'm focusing on user control.

**Analyzing Library Initialization**

I've been examining how `three.min.js` initializes. It exports `THREE` as a CommonJS module, or makes it globally available if loaded in a browser. Specifically, when using a script tag in the browser, `THREE` attaches to the `window` object. Now I'm shifting focus toward designing the Rubik's Cube implementation. I'm focusing on the cube's representation first.


**Defining Cubie Geometry**

I'm now thinking about the Rubik's Cube's visual representation. I'll use 27 cubies at grid positions, excluding the center. Each cubie will be a `THREE.Mesh` using either a rounded or standard box geometry, potentially with slight gaps between to avoid visual artifacts. The colors will follow standard Rubik's Cube color conventions, and inner faces will be dark gray or black.


**Implementing Cube Rotations**

I'm now focusing on how the cube will rotate. I've broken down the moves: `U`, `D`, `F`, `B` are rotations around Y. `R`, `L` around X. Prime moves reverse direction, and double moves are 180 degrees. To make it smooth, I'll create a temporary pivot group for the cubies in a slice, animate it with `requestAnimationFrame`, then update cubie positions mathematically once complete, and manage the move queue.


**Designing User Interface**

I'm now focusing on the user interface design. I'm planning a clean, modern style using Tailwind-like classes or custom CSS with a dark theme and nice elements. The 3D viewport will fill the screen, or be centered. I'll include a control panel with logically grouped face rotation buttons, action buttons for Scramble, Reset, Solve, and speed selection. I plan to display move count, a timer, and status updates, along with instructions. Dragging the cube should also trigger rotations.