I'm having difficulty assigning separate connections between the javascript and input range sliders. I realize there's no designation call to the sliders as needed. My knowledge is limited.

Only one function works. Where and how do I add that class name into the javascript so that each slider operates according to it's getElementID?

SEE Troubled Example ~ :
http://codepen.io/anon/pen/yLKcu

Thanks i'll unobtrusively await your feedback.
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