gistfile1.js

// Nikita Lebedev's blog, nazz.me/simple-jquery-popup
(function($) {
  $.fn.simplePopup = function() {

    var simplePopup = {

      // Events
      initialize: function(self) {

        var popup = $(".js__popup");
        var body = $(".js__p_body");
        var close = $(".js__p_close");

        var string = self[0].className;
        var name = string.replace("js__p_", "");

        // We redefine the variables if there is an additional popap
        if ( !(name === "start") ) {
          name = name.replace("_start", "_popup");
          popup = $(".js__" + name);
          name = name.replace("_", "-");
        };

        // Call when have click
        self.on("click", function() {
          simplePopup.show(popup, body);
          return false;
        });

        // Close
        body.on("click", function() {
          simplePopup.hide(popup, body);
        });

        close.on("click", function() {
          simplePopup.hide(popup, body);
          return false;
        });

        // Closure of the button "esc"
        $(window).keyup(function(e) {
          if (e.keyCode === 27) {
            simplePopup.hide(popup, body);
          }
        });

      },

      // Centering method
      centering: function(self) {
        var marginLeft = -self.width()/2;
        return self.css("margin-left", marginLeft);
      },

      // The overall function of the show
      show: function(popup, body) {
        simplePopup.centering(popup);
        body.removeClass("js__fadeout");
        popup.removeClass("js__slide_top");
      },

      // The overall function of the hide
      hide: function(popup, body) {
        popup.addClass("js__slide_top");
        body.addClass("js__fadeout");

      },

    };

    // In loop looking for what is called
    return this.each(function() {
      var self = $(this);
      simplePopup.initialize(self);
    });

  };
})(jQuery);