Use this MotionSites background video as a looping website background asset. Title: Fluid Motion Category: background License: 免费 Video URL: https://d8j0ntlcm91z4.cloudfront.net/user_38xzZboKViGWJOttwIXH07lWA1P/hf_20260406_133058_0504132a-0cf3-4450-a370-8ea3b05c95d4.mp4 Local thumbnail: thumbnails/20ca1b25-8ae2-4355-ae80-c89fe1184683.jpg Implementation requirements: - Render the video as a muted, autoplay, looped, playsInline background layer. - Use object-fit: cover and keep the focal motion visible on desktop and mobile. - Add a readable overlay only when foreground text needs contrast. - Keep controls hidden for decorative background use, and provide a poster/thumbnail fallback. - Respect the MotionSites authorization state before using this asset in a commercial project.