Update the background

[ZHaiiiNINnnG]

Newly Added Content

1. Deep Space Gradient Background
   • Added a multi-layer radial gradient background to replace the plain black grid.
   • Introduced dark blue and black tones to simulate cosmic depth.

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2. High-Density Star Field
   • Added multiple layers of stars using radial-gradient.
   • Included stars of different sizes and brightness levels.
   • Increased overall star density to make the background visually rich.

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3. Star Drift Animation
   • Added a slow vertical drifting animation to the star field.
   • Simulates large-scale movement in outer space.

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4. Star Twinkling Effect
   • Introduced an opacity-based animation to make stars flicker subtly.
   • Enhances realism without affecting foreground animations.

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5. Solar Corona (Inner Solar Flare)
   • Added an inner glowing corona around the Sun using a pseudo-element.
   • Applied pulsing scale and opacity animation.

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6. Outer Solar Energy Wave
   • Added an outer, blurred energy halo around the Sun.
   • Simulates solar flare expansion and energy radiation.

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7. Layered Visual Structure
   • Introduced background layers using ::before and z-index.
   • Clearly separated background, stars, and celestial bodies.