I didn't realize that you wanted the DateInput control to be initially
not visible. Indeed, in this case the visibility toggling on the client is not that easy (and ellegant) to achieve, unless you place the RadDateInput inside some other element (e.g. a <div> or <span>) and toggle its visibility instead.
"the input appears and disappears when I hover over it" - this is because the control remembers its initial style settings and they are reapplied onmouseover, mouseout, focus, etc. Otherwise the custom styles set on the server would be lost, which is not expected.
Generally, when you want to change the inline textbox styles, you should do it in a special way and call updateCssClass() afterwards. Here is an example:
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