The best option is to buy some ready.
There are several in the market and many use Bootstrap.
And with costs starting at $ 3.00 ($ 12.00 for a responsive template) it's banana price.
NOTE: Many come from pure html, version for php, ajax, .net, angular.js,
less, sass, etc.
But even if it does not come ready in php to migrate an html will not be any difficult task.
Even if you do not use it fully, it ends up serving as a library of plugins, css, widget, etc. It can be very useful to buy 2 or 3 of them to dismember and make your system with several pieces.
link
There are several other sites, but the only one I recommend is this one.
Disadvantage : The only disadvantage I can find is that many end up abusing the use of plugins so they usually have thousands of .js together, but nothing that a few hours you can not remove and leave only what wish.
Below are the versions of a layout purchased at the link above: