/*!
 * headroom.js v0.7.0 - 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(b) { return b && "undefined" != typeof a && (b === a || b.nodeType) } function e(a) { if (arguments.length <= 0) throw new Error("Missing arguments in extend function"); var b, c, f = a || {}; for (c = 1; c < arguments.length; c++) { var g = arguments[c] || {}; for (b in g) f[b] = "object" != typeof f[b] || d(f[b]) ? f[b] || g[b] : e(f[b], g[b]) } return f } function f(a) { return a === Object(a) ? a : { down: a, up: a } } function g(a, b) { b = e(b, g.options), this.lastKnownScrollY = 0, this.elem = a, this.debouncer = new c(this.update.bind(this)), this.tolerance = f(b.tolerance), this.classes = b.classes, this.offset = b.offset, this.scroller = b.scroller, this.initialised = !1, this.onPin = b.onPin, this.onUnpin = b.onUnpin, this.onTop = b.onTop, this.onNotTop = b.onNotTop } var h = { 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() } }, g.prototype = { constructor: g, init: function () { return g.cutsTheMustard ? (this.elem.classList.add(this.classes.initial), setTimeout(this.attachEvent.bind(this), 100), this) : void 0 }, destroy: function () { var a = this.classes; this.initialised = !1, this.elem.classList.remove(a.unpinned, a.pinned, a.top, a.initial), this.scroller.removeEventListener("scroll", this.debouncer, !1) }, attachEvent: function () { this.initialised || (this.lastKnownScrollY = this.getScrollY(), this.initialised = !0, this.scroller.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 !== this.scroller.pageYOffset ? this.scroller.pageYOffset : void 0 !== this.scroller.scrollTop ? this.scroller.scrollTop : (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) }, getElementHeight: function (a) { return Math.max(a.scrollHeight, a.offsetHeight, a.clientHeight) }, getScrollerHeight: function () { return this.scroller === a || this.scroller === b.body ? this.getDocumentHeight() : this.getElementHeight(this.scroller) }, isOutOfBounds: function (a) { var b = 0 > a, c = a + this.getViewportHeight() > this.getScrollerHeight(); 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) } }, g.options = { tolerance: { up: 0, down: 0 }, offset: 0, scroller: a, classes: { pinned: "headroom--pinned", unpinned: "headroom--unpinned", top: "headroom--top", notTop: "headroom--not-top", initial: "headroom" } }, g.cutsTheMustard = "undefined" != typeof h && h.rAF && h.bind && h.classList, a.Headroom = g }(window, document);