Minimalist modal range slider

This is rebound of one of my own shot.
Its a minimalist modal slider UI element, made with css only, no images, no javascript.

I would like to make it more simple than the first one, so I decide to upload my changes here.
Feel free to comment and share.

Make sure to view the : Online version(webkit only)

Update : The background seems to be a "step-gradient" if I may say so. It's because I took a screen shot of the online version.

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