Misuzu.Events.Christmas2019 = function() { this.propName = propName = 'msz-christmas-' + (new Date).getFullYear().toString(); }; Misuzu.Events.Christmas2019.prototype.changeColour = function() { var count = parseInt(localStorage.getItem(this.propName)); document.body.style.setProperty('--header-accent-colour', (count++ % 2) ? 'green' : 'red'); localStorage.setItem(this.propName, count.toString()); }; Misuzu.Events.Christmas2019.prototype.isActive = function() { var d = new Date; return d.getMonth() === 11 && d.getDate() > 5 && d.getDate() < 27; }; Misuzu.Events.Christmas2019.prototype.dispatch = function() { var headerBg = $q('.header__background'), menuBgs = $qa('.header__desktop__submenu__background'); if(!localStorage.getItem(this.propName)) localStorage.setItem(this.propName, '0'); if(headerBg) headerBg.style.transition = 'background-color .4s'; setTimeout(function() { if(headerBg) headerBg.style.transition = 'background-color 1s'; for(var i = 0; i < menuBgs.length; i++) menuBgs[i].style.transition = 'background-color 1s'; }, 1000); this.changeColour(); setInterval(this.changeColour, 10000); };