/*!

 * headroom.js v0.6.0 - give your page some headroom. hide your header until you need it

 * copyright (c) 2014 nick williams - http://wicky.nillia.ms/headroom.js

 * license: mit

 */

 

!function(a,b){"use strict";function c(a){this.callback=a,this.ticking=!1}function d(a){if(arguments.length<=0)throw new error("missing arguments in extend function");var b,c,e=a||{};for(c=1;c<arguments.length;c++){var f=arguments[c]||{};for(b in f)e[b]="object"==typeof e[b]?d(e[b],f[b]):e[b]||f[b]}return e}function e(a){return a===object(a)?a:{down:a,up:a}}function f(a,b){b=d(b,f.options),this.lastknownscrolly=0,this.elem=a,this.debouncer=new c(this.update.bind(this)),this.tolerance=e(b.tolerance),this.classes=b.classes,this.offset=b.offset,this.initialised=!1,this.onpin=b.onpin,this.onunpin=b.onunpin,this.ontop=b.ontop,this.onnottop=b.onnottop}var g={bind:!!function(){}.bind,classlist:"classlist"in b.documentelement,raf:!!(a.requestanimationframe||a.webkitrequestanimationframe||a.mozrequestanimationframe)};a.requestanimationframe=a.requestanimationframe||a.webkitrequestanimationframe||a.mozrequestanimationframe,c.prototype={constructor:c,update:function(){this.callback&&this.callback(),this.ticking=!1},requesttick:function(){this.ticking||(requestanimationframe(this.rafcallback||(this.rafcallback=this.update.bind(this))),this.ticking=!0)},handleevent:function(){this.requesttick()}},f.prototype={constructor:f,init:function(){return f.cutsthemustard?(this.elem.classlist.add(this.classes.initial),settimeout(this.attachevent.bind(this),100),this):void 0},destroy:function(){var b=this.classes;this.initialised=!1,a.removeeventlistener("scroll",this.debouncer,!1),this.elem.classlist.remove(b.unpinned,b.pinned,b.top,b.initial)},attachevent:function(){this.initialised||(this.lastknownscrolly=this.getscrolly(),this.initialised=!0,a.addeventlistener("scroll",this.debouncer,!1),this.debouncer.handleevent())},unpin:function(){var a=this.elem.classlist,b=this.classes;(a.contains(b.pinned)||!a.contains(b.unpinned))&&(a.add(b.unpinned),a.remove(b.pinned),this.onunpin&&this.onunpin.call(this))},pin:function(){var a=this.elem.classlist,b=this.classes;a.contains(b.unpinned)&&(a.remove(b.unpinned),a.add(b.pinned),this.onpin&&this.onpin.call(this))},top:function(){var a=this.elem.classlist,b=this.classes;a.contains(b.top)||(a.add(b.top),a.remove(b.nottop),this.ontop&&this.ontop.call(this))},nottop:function(){var a=this.elem.classlist,b=this.classes;a.contains(b.nottop)||(a.add(b.nottop),a.remove(b.top),this.onnottop&&this.onnottop.call(this))},getscrolly:function(){return void 0!==a.pageyoffset?a.pageyoffset:(b.documentelement||b.body.parentnode||b.body).scrolltop},getviewportheight:function(){return a.innerheight||b.documentelement.clientheight||b.body.clientheight},getdocumentheight:function(){var a=b.body,c=b.documentelement;return math.max(a.scrollheight,c.scrollheight,a.offsetheight,c.offsetheight,a.clientheight,c.clientheight)},isoutofbounds:function(a){var b=0>a,c=a+this.getviewportheight()>this.getdocumentheight();return b||c},toleranceexceeded:function(a,b){return math.abs(a-this.lastknownscrolly)>=this.tolerance[b]},shouldunpin:function(a,b){var c=a>this.lastknownscrolly,d=a>=this.offset;return c&&d&&b},shouldpin:function(a,b){var c=a<this.lastknownscrolly,d=a<=this.offset;return c&&b||d},update:function(){var a=this.getscrolly(),b=a>this.lastknownscrolly?"down":"up",c=this.toleranceexceeded(a,b);this.isoutofbounds(a)||(a<=this.offset?this.top():this.nottop(),this.shouldunpin(a,c)?this.unpin():this.shouldpin(a,c)&&this.pin(),this.lastknownscrolly=a)}},f.options={tolerance:{up:0,down:0},offset:0,classes:{pinned:"headroom--pinned",unpinned:"headroom--unpinned",top:"headroom--top",nottop:"headroom--not-top",initial:"headroom"}},f.cutsthemustard="undefined"!=typeof g&&g.raf&&g.bind&&g.classlist,a.headroom=f}(window,document);