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HTML

              
                - var categories=[{id:1,name:"Activities"},{id:2,name:"Frontend"},{id:3,name:"Backend"},{id:4,name:"QA"},{id:5,name:"Mobile"},{id:6,name:"Teamlead"},{id:7,name:"Future"}];
- var schedule=[{date:"30 March",periods:[{timeStart:"10:30",timeEnd:"10:45",status:"completed",events:[{title:"Grand opening",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Hall #1",isAddedToFavorites:!1,backgroundId:1}]},{timeStart:"10:50",timeEnd:"11:30",status:"completed",events:[{title:"Тренды невозможного",link:"#",categoryId:7,speakerName:"Евгений Черешнев",speakerImage:"https://2019.codefest.ru/upload/members/photo_1548787955_200.jpg",speakerCompany:"Biolink.Tech",location:"Hangar",isAddedToFavorites:!0,backgroundId:""},{title:"Рефакторинг: договариваемся, планируем, внедряем!",link:"#",categoryId:6,speakerName:"Алексей Катаев",speakerImage:"https://2019.codefest.ru/upload/members/photo_1547747987_200.jpg",speakerCompany:"Skyeng",location:"Hall #3",isAddedToFavorites:!1,backgroundId:""},{title:"Code Battle",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Wrike stand",isAddedToFavorites:!0,backgroundId:2},{title:"May the F[_] be with You. Функциональный подход к проектированию API",link:"#",categoryId:3,speakerName:"Иван Фастов",speakerImage:"https://2019.codefest.ru/upload/members/photo_1551973214_200.jpg",speakerCompany:"Тинькофф",location:"Hall #4",isAddedToFavorites:!1,backgroundId:""}]},{timeStart:"11:00",timeEnd:"11:30",status:"completed",events:[{title:"Просмотр фильма о дизайнерах-маньяках",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Yandex stand",isAddedToFavorites:!1,backgroundId:3}]},{timeStart:"11:50",timeEnd:"12:30",status:"active",events:[{title:"Сжимаем Javascript по-взрослому",link:"#",categoryId:2,speakerName:"Алексей Золотых",speakerImage:"https://2019.codefest.ru/upload/members/photo_1552416059_200.jpg",speakerCompany:"Infobip",location:"Hall #2",isAddedToFavorites:!0,backgroundId:""},{title:"Context: The missing ingredient in multilingual software translation",link:"#",categoryId:4,speakerName:"Mirjana Andovska",speakerImage:"https://2019.codefest.ru/upload/members/photo_1546541112_200.jpg",speakerCompany:"Netcetera",location:"Hall #1",isAddedToFavorites:!1,backgroundId:""},{title:"iOS. Переход на тёмную сторону",link:"#",categoryId:5,speakerName:"Антон Спивак",speakerImage:"https://2019.codefest.ru/upload/members/photo_1550597366_200.jpg",speakerCompany:"ВКонтакте",location:"Hall #7",isAddedToFavorites:!1,backgroundId:""}]},{timeStart:"12:30",timeEnd:"13:00",status:"coming",events:[{title:"Wrike Garage game",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Wrike stand",isAddedToFavorites:!1,backgroundId:4}]},{timeStart:"13:00",timeEnd:"13:50",status:"coming",events:[{title:"Forward-looking city making",link:"#",categoryId:7,speakerName:"Daniela Allmeier",speakerImage:"https://2019.codefest.ru/upload/members/photo_1549301703_200.jpg",speakerCompany:"RAUMPOSITION",location:"Hangar",isAddedToFavorites:!1,backgroundId:""},{title:"Эффективные 1-на-1",link:"#",categoryId:6,speakerName:"Георгий Могелашвили",speakerImage:"https://2019.codefest.ru/upload/members/photo_1545919642_200.jpg",speakerCompany:"Booking.com",location:"Hall #3",isAddedToFavorites:!1,backgroundId:""},{title:"Инструментирование Go кода",link:"#",categoryId:3,speakerName:"Максим Чечель",speakerImage:"https://2019.codefest.ru/upload/members/photo_1550689359_200.jpg",speakerCompany:"Juno",location:"Hall #4",isAddedToFavorites:!1,backgroundId:""}]}]},{date:"31 March",periods:[{timeStart:"10:30",timeEnd:"11:20",status:"coming",events:[{title:"Beyond Web-Apps: WebAssembly, JS and React to rewrite native apps",link:"#",categoryId:2,speakerName:"Florian Rival",speakerImage:"https://2019.codefest.ru/upload/members/photo_1548181969_200.jpg",speakerCompany:"Facebook",location:"Hall #5",isAddedToFavorites:!0,backgroundId:""},{title:"Как превратить QA команду в руины?",link:"#",categoryId:4,speakerName:"Юлия Долбилова",speakerImage:"https://2019.codefest.ru/upload/members/photo_1547744684_200.jpg",speakerCompany:"Додо Пицца",location:"Hall #6",isAddedToFavorites:!1,backgroundId:""},{title:"iOS. Функциональный Swift — это просто",link:"#",categoryId:5,speakerName:"Евгений Ёлчев",speakerImage:"https://2019.codefest.ru/upload/members/photo_1547748822_200.jpg",speakerCompany:"RedMadRobot",location:"Hall #7",isAddedToFavorites:!1,backgroundId:""}]},{timeStart:"11:00",timeEnd:"11:30",status:"coming",events:[{title:"SberQuiz",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Sberbank stand",isAddedToFavorites:!1,backgroundId:5}]},{timeStart:"11:30",timeEnd:"12:20",status:"coming",events:[{title:"Эволюция цифрового общения",link:"#",categoryId:7,speakerName:"Виктор Иванов",speakerImage:"https://2019.codefest.ru/upload/members/photo_1550080274_200.jpg",speakerCompany:"ВКонтакте",location:"Hangar",isAddedToFavorites:!1,backgroundId:""},{title:"Terraform на примере кластера Selenoid",link:"#",categoryId:4,speakerName:"Леонид Руденко",speakerImage:"https://2019.codefest.ru/upload/members/photo_1548440624_200.jpg",speakerCompany:"JetBrains",location:"Hall #6",isAddedToFavorites:!1,backgroundId:""},{title:"Android. Instant Apps — два года спустя",link:"#",categoryId:5,speakerName:"Евгений Сатуров",speakerImage:"https://2019.codefest.ru/upload/members/photo_1547746474_200.jpg",speakerCompany:"Surf",location:"Hall #7",isAddedToFavorites:!1,backgroundId:""}]},{timeStart:"12:00",timeEnd:"12:30",status:"coming",events:[{title:"Hundred to One",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"VK stand",isAddedToFavorites:!0,backgroundId:6}]},{timeStart:"12:30",timeEnd:"13:20",status:"coming",events:[{title:"Ultimate React Component Patterns with TypeScript",link:"#",categoryId:2,speakerName:"Martin Hochel",speakerImage:"https://2019.codefest.ru/upload/members/photo_1548267264_200.jpg",speakerCompany:"Twisto.cz, ngParty",location:"Hall #5",isAddedToFavorites:!1,backgroundId:""},{title:"Тестирование мусорными данными с libFuzzer",link:"#",categoryId:4,speakerName:"Дмитрий Тримонов",speakerImage:"https://2019.codefest.ru/upload/members/photo_1548953275_200.jpg",speakerCompany:"2ГИС",location:"Hall #6",isAddedToFavorites:!1,backgroundId:""},{title:"iOS. Rx в современной мобильной разработке. Есть ли смысл?",link:"#",categoryId:5,speakerName:"Евгений Сатуров",speakerImage:"https://2019.codefest.ru/upload/members/photo_1550598154_200.jpg",speakerCompany:"Яндекс",location:"Hall #7",isAddedToFavorites:!1,backgroundId:""}]},{timeStart:"13:30",timeEnd:"13:45",status:"coming",events:[{title:"Сlosing and awarding of the winners",link:"#",categoryId:1,speakerName:"",speakerImage:"",speakerCompany:"",location:"Hall #1",isAddedToFavorites:!1,backgroundId:7}]}]}];

.app

  //- offcanvas
  .app__offcanvas.offcanvas(
    id="offcanvas"
    aria-hidden="true")
    
    .offcanvas__overlay(
      tabindex="-1"
      data-micromodal-close)
      
      //- sidepanel
      .offcanvas__panel.sidepanel(
        role="dialog"
        aria-labelledby="navigation-title"
        data-micromodal-dialog)

        .sidepanel__container
          
          h2.visually-hidden(
            id="navigation-title") Navigation
        
          svg.sidepanel__logo(
            height="61" viewBox="0 0 54 61"
            role="img"
            aria-label="Codefest logo")
            path(
              fill="#33a7d8"
              d="M39.4.31L8.15 16.34V49.7l3.4 1.2v8.81L17.5 53l22.2 7.86a2.5 2.5 0 003.3-2.4V2.58A2.48 2.48 0 0039.4.31")
            path(
              d="M32.12 17.8L2.83 14.02c-1.5-.2-2.83 1-2.83 2.54v31.88c0 1.5 1.26 2.68 2.73 2.55l29.3-2.61A2.18 2.18 0 0034 46.19V20c0-1.12-.8-2.05-1.88-2.19")
            path(
              fill="#fff"
              d="M22.81 40.22c0 1.8-1.19 2.71-2.49 2.8-1.03.08-1.84-.11-2.4-.57v-2.48c.6.6 1.58.96 2.31.92.45-.03.68-.3.68-.57 0-1.06-3.05-.53-3.05-3.31 0-1.68 1-2.7 2.6-2.7a2.9 2.9 0 012.06.75v2.32c-.62-.58-1.28-.99-1.98-.97-.42 0-.63.29-.63.56 0 .96 2.9.25 2.9 3.25zM26 34.49l1.28-.01v2.07l-1.28.03v2.83c0 .69.17.94.6.92.23-.01.46-.12.68-.31v2.04c-.3.33-.73.52-1.28.56-1.05.07-1.79-.8-1.8-2.5v-3.5l-.92.02V34.5h.92v-2.16l1.8.03v2.12zM3.7 32.77l7.1.06v2.62l-4.61.05v1.87l3.47-.08v2.54l-3.47.15v3.84L3.7 44V32.77zm9.3 5.29c.09-1 .5-1.63 1.07-1.64.52 0 .95.63.96 1.57l-2.03.07zm1.17-3.74c-2.14 0-3.32 2.15-3.32 4.7 0 2.97 1.54 4.58 3.5 4.44a3.26 3.26 0 002.38-1.07v-2.28c-.62.52-1.27.8-1.92.84-.88.05-1.6-.36-1.8-1.27l4.05-.17v-.74c0-2.44-1-4.45-2.89-4.45zm-3.38-8.09v3.1a4.04 4.04 0 01-2.87 1.05c-2.7-.07-4.92-2.42-4.92-6 0-3.56 2.18-5.64 4.9-5.35a4.4 4.4 0 012.74 1.33v2.93a4.1 4.1 0 00-2.7-1.46c-1.4-.12-2.56.95-2.56 2.7 0 1.83 1.2 2.98 2.64 3.05a3 3 0 002.77-1.35zm17-.24c.06-.88.39-1.4.84-1.37.4.03.75.63.76 1.47l-1.6-.1zm3.2.96c0-2.17-.8-4.05-2.29-4.2-1.7-.15-2.62 1.66-2.62 3.92v.25c.01.31.04.61.09.9v.04l.03.15c.34 1.82 1.38 2.85 2.64 2.89.88.02 1.45-.24 1.9-.75v-2.04c-.5.42-1.01.62-1.53.6a1.45 1.45 0 01-1.42-1.28l3.21.17v-.65zm-8.7 1.5c-.67-.02-1.14-.91-1.14-2.08 0-1.16.47-2 1.14-1.94.48.03.82.37 1.07 1v2.15c-.24.6-.59.9-1.06.88zm1.07 2.1l1.82.05-.01-10.3-1.82-.2v3.27c-.37-.78-.91-1.2-1.6-1.27-1.57-.14-2.54 1.88-2.53 4.16 0 2.27.94 4.42 2.53 4.46.7.01 1.24-.34 1.61-1.08v.91zm-8.15-2.42c-.78-.03-1.35-.96-1.35-2.2 0-1.19.57-2.09 1.34-2.03.77.06 1.32 1.02 1.32 2.2 0 1.2-.55 2.06-1.31 2.03zm0-6.64c-2-.2-3.49 1.67-3.49 4.32 0 2.6 1.43 4.69 3.49 4.74 1.99.05 3.3-1.86 3.3-4.34 0-2.5-1.37-4.54-3.3-4.72z")

          nav.sidepanel__menu.menu(
            aria-label="Main")
            ul.menu__list
              li.menu__item
                a.menu__link.menu__link--active(
                  href="#") Schedule
              li.menu__item
                a.menu__link(
                  href="#") Map
              li.menu__item
                a.menu__link(
                  href="#") Notifications
              li.menu__item
                a.menu__link(
                  href="#") Updates

          .sidepanel__user.user
            img.user__image(
              src="https://randomuser.me/api/portraits/women/13.jpg"
              width="48" height="48"
              alt="")
            .user__name
              span.visually-hidden Username: 
              | snowflake
            button.user__button Sign out

          button.sidepanel__theme-switcher.theme-switcher(
            type="button"
            aria-label="Switch to dark theme")
            svg.theme-switcher__icon(
              width="16" height="16" viewBox="0 0 512 512"
              aria-hidden="true")
              path.theme-switcher__icon-sun(
                d="M256 160c-52.9 0-96 43.1-96 96s43.1 96 96 96 96-43.1 96-96-43.1-96-96-96zm246.4 80.5l-94.7-47.3 33.5-100.4c4.5-13.6-8.4-26.5-21.9-21.9l-100.4 33.5-47.4-94.8c-6.4-12.8-24.6-12.8-31 0l-47.3 94.7L92.7 70.8c-13.6-4.5-26.5 8.4-21.9 21.9l33.5 100.4-94.7 47.4c-12.8 6.4-12.8 24.6 0 31l94.7 47.3-33.5 100.5c-4.5 13.6 8.4 26.5 21.9 21.9l100.4-33.5 47.3 94.7c6.4 12.8 24.6 12.8 31 0l47.3-94.7 100.4 33.5c13.6 4.5 26.5-8.4 21.9-21.9l-33.5-100.4 94.7-47.3c13-6.5 13-24.7.2-31.1zm-155.9 106c-49.9 49.9-131.1 49.9-181 0-49.9-49.9-49.9-131.1 0-181 49.9-49.9 131.1-49.9 181 0 49.9 49.9 49.9 131.1 0 181z")
              path.theme-switcher__icon-moon(
                d="M283.211 512c78.962 0 151.079-35.925 198.857-94.792 7.068-8.708-.639-21.43-11.562-19.35-124.203 23.654-238.262-71.576-238.262-196.954 0-72.222 38.662-138.635 101.498-174.394 9.686-5.512 7.25-20.197-3.756-22.23A258.156 258.156 0 0 0 283.211 0c-141.309 0-256 114.511-256 256 0 141.309 114.511 256 256 256z")
          
          button.sidepanel__close-button.visually-hidden-focusable(
            type="button"
            data-micromodal-close) Close navigation
  
  //- content 
  .app__content.js-app-content
      
    //- header
    header.app__header.header
      
      button.header__button.header__button-nav(
        type="button"
        aria-label="Open navigation"
        data-micromodal-trigger="offcanvas")
        span.header__button-icon.burger
          span.burger__bar
      
      button.header__button.header__button-search(
        type="button"
        aria-label="Open search field")
        svg.header__button-icon(
          width="16" height="16" viewBox="0 0 512 512"
          aria-hidden="true")
          path(
            d="M508.5 468.9L387.1 347.5c-2.3-2.3-5.3-3.5-8.5-3.5h-13.2c31.5-36.5 50.6-84 50.6-136C416 93.1 322.9 0 208 0S0 93.1 0 208s93.1 208 208 208c52 0 99.5-19.1 136-50.6v13.2c0 3.2 1.3 6.2 3.5 8.5l121.4 121.4c4.7 4.7 12.3 4.7 17 0l22.6-22.6c4.7-4.7 4.7-12.3 0-17zM208 368c-88.4 0-160-71.6-160-160S119.6 48 208 48s160 71.6 160 160-71.6 160-160 160z")

      h1.header__title Schedule

    //- filters
    fieldset.content__filters.filters
      
      legend.visually-hidden
        h2 Events display filter

      .filters__wrapper
        .filters__container
      
          .filters__item
            input.filters__input.js-filter(
              id="filter-all"
              type="radio"
              name="filter"
              value=""
              checked)
            label.filters__button(
              for="filter-all") All

          .filters__item
            input.filters__input.js-filter(
              id="filter-favorites"
              type="radio"
              name="filter"
              value="favorites")
            label.filters__button.filters__button--has-icon(
              for="filter-favorites")
              svg.filters__button-icon(
                width="16" height="16" viewBox="0 0 576 512"
                aria-hidden="true")
                path(
                  d="M259.3 17.8L194 150.2 47.9 171.5c-26.2 3.8-36.7 36.1-17.7 54.6l105.7 103-25 145.5c-4.5 26.3 23.2 46 46.4 33.7L288 439.6l130.7 68.7c23.2 12.2 50.9-7.4 46.4-33.7l-25-145.5 105.7-103c19-18.5 8.5-50.8-17.7-54.6L382 150.2 316.7 17.8c-11.7-23.6-45.6-23.9-57.4 0z")
              | Favorites

          .filters__item
            input.filters__input.js-filter(
              id="filter-live"
              type="radio"
              name="filter"
              value="live")
            label.filters__button.filters__button--has-icon(
              for="filter-live")
              svg.filters__button-icon(
                width="16" height="16" viewBox="0 0 576 512" aria-hidden="true")
                path(
                  d="M186.87 157.25l-11.37-11.11a16.44 16.44 0 0 0-24 1.3 168.83 168.83 0 0 0 0 217.12 16.44 16.44 0 0 0 24 1.3l11.37-11.11a15.14 15.14 0 0 0 1.29-20.53 122.72 122.72 0 0 1 0-156.44 15.15 15.15 0 0 0-1.29-20.53zM107.33 79.6L96 68.53a16.41 16.41 0 0 0-23.56 1C25.59 121 0 186.58 0 256s25.59 135 72.44 186.52a16.41 16.41 0 0 0 23.56 1l11.33-11.07c6.11-6 6.06-15.39.36-21.71a230.28 230.28 0 0 1 0-309.37c5.7-6.37 5.75-15.81-.36-21.77zm396.23-10.12a16.41 16.41 0 0 0-23.56-1L468.67 79.6c-6.11 6-6.06 15.39-.36 21.72a230.28 230.28 0 0 1 0 309.37c-5.7 6.32-5.75 15.75.36 21.71L480 443.47a16.41 16.41 0 0 0 23.56-1C550.41 391 576 325.42 576 256s-25.59-135-72.44-186.52zM288 200a56 56 0 1 0 56 56 56 56 0 0 0-56-56zm112.5-53.86l-11.37 11.11a15.15 15.15 0 0 0-1.29 20.53 122.72 122.72 0 0 1 0 156.44 15.15 15.15 0 0 0 1.29 20.53l11.37 11.11a16.44 16.44 0 0 0 24-1.3 168.83 168.83 0 0 0 0-217.12 16.44 16.44 0 0 0-24-1.3z")
              | Going now
          
          each category in categories
            .filters__item
              input.filters__input.js-filter(
                id=`filter-${category.id}`
                type="radio"
                name="filter"
                value=`category-${category.id}`)
              label.filters__button(
                class= category.id == "1" ? "filters__button--has-icon" : false
                class=`category--${category.id}`
                for=`filter-${category.id}`)
                if category.id == "1"
                  svg.filters__button-icon(
                    width="16" height="16" viewBox="0 0 640 512"
                    aria-hidden="true")
                    path(
                      d="M400 224a32 32 0 1 0 32 32 32 32 0 0 0-32-32zm238.57 114.4l-27.5-181.25C603.32 106 565.45 65 515.68 53.79a889.52 889.52 0 0 0-391.36 0C74.55 65 36.68 106 28.93 157.15L1.44 338.4C-9.86 412.85 46.94 480 121.21 480h.25a121 121 0 0 0 108.38-67.94L243.67 384h152.66l13.83 28.06A121 121 0 0 0 518.55 480h.25c74.27 0 131.06-67.15 119.77-141.6zm-64.85 68.19A71.66 71.66 0 0 1 518.55 432c-27.79 0-52.82-15.77-65.34-41.17l-13.83-28.05-13.2-26.78H213.82l-13.2 26.78-13.83 28.05c-12.52 25.4-37.55 41.17-65.58 41.17a71.55 71.55 0 0 1-54.93-25.41 76 76 0 0 1-17.39-61l27.49-181.24c4.83-31.8 27.79-56.82 58.5-63.74a841.73 841.73 0 0 1 370.25 0c30.71 6.92 53.66 31.94 58.49 63.74l27.49 181.25a76 76 0 0 1-17.39 60.99zM496 160a32 32 0 1 0 32 32 32 32 0 0 0-32-32zm-232 40h-48v-48a8 8 0 0 0-8-8h-32a8 8 0 0 0-8 8v48h-48a8 8 0 0 0-8 8v32a8 8 0 0 0 8 8h48v48a8 8 0 0 0 8 8h32a8 8 0 0 0 8-8v-48h48a8 8 0 0 0 8-8v-32a8 8 0 0 0-8-8z")
                | #{category.name}

    //- schedule     
    .content__schedule.schedule
      
      //- day
      each day in schedule
        section.section-day
          h2.section-day__title
            time.section-day__title-text= day.date

          .section-day__content
            
            //- period
            each period, index in day.periods
              section.section-period
                h3.period-time(
                  id=`period-${index}`
                  class=`period-time--${period.status}`)
                  time.period-time__text(
                    role="text")
                    span.period-time__start= period.timeStart
                    span.visually-hidden  — 
                    span.period-time__end= period.timeEnd
                
                ul.section-period__events(
                  aria-labelledby=`period-${index}`)
                  
                  //- event
                  each event in period.events
                    each category in categories
                      if category.id == event.categoryId
                        li.section-period__event.event(
                          class=`event--category-${category.id}`
                          class= category.id == "1" ? `event--activity event--background-${event.backgroundId}` : false
                          data-filter=`category-${category.id}`
                          data-favorite= event.isAddedToFavorites ? '' : false
                          data-live= period.status == 'active' ? '' : false)
                          
                          //- title
                          h3.event__title
                            a.event__link(href= event.link)= event.title

                          //- meta
                          .event__meta.meta
                            .meta__item
                              span.visually-hidden Location: 
                              | #{event.location}
                            if category.id != "1"
                              .meta__item(
                                aria-hidden="true") ·
                              .meta__item(
                                class=`category--${category.id}`)
                                span.visually-hidden Category: 
                                | #{category.name}
                            else
                              .visually-hidden=`Category: ${category.name}`

                          //- author
                          if category.id != "1"
                            .author
                              img.author__image(
                                src= event.speakerImage
                                width="48" height="48"
                                alt="")
                              .author__name
                                span.visually-hidden Speaker: 
                                | #{event.speakerName}
                              .author__company
                                span.visually-hidden Company: 
                                | #{event.speakerCompany}

                          //- favorite button
                          button.event__favorite-button.favorite-button(
                            class= event.isAddedToFavorites ? "favorite-button--active" : null
                            data-favorite= event.isAddedToFavorites
                            aria-label= event.isAddedToFavorites ? `Remove "${event.title}" from favorites` : `Add "${event.title}" to favorites` 
                            type="button")
                            svg(
                              class="favorite-button__icon"
                              width="16" height="16" viewBox="0 0 576 512"
                              aria-hidden="true")
                              path.favorite-button__icon-stroke(
                                d="M528.1 171.5L382 150.2 316.7 17.8c-11.7-23.6-45.6-23.9-57.4 0L194 150.2 47.9 171.5c-26.2 3.8-36.7 36.1-17.7 54.6l105.7 103-25 145.5c-4.5 26.3 23.2 46 46.4 33.7L288 439.6l130.7 68.7c23.2 12.2 50.9-7.4 46.4-33.7l-25-145.5 105.7-103c19-18.5 8.5-50.8-17.7-54.6zM388.6 312.3l23.7 138.4L288 385.4l-124.3 65.3 23.7-138.4-100.6-98 139-20.2 62.2-126 62.2 126 139 20.2-100.6 98z")
                              path.favorite-button__icon-filled(
                                d="M259.3 17.8L194 150.2 47.9 171.5c-26.2 3.8-36.7 36.1-17.7 54.6l105.7 103-25 145.5c-4.5 26.3 23.2 46 46.4 33.7L288 439.6l130.7 68.7c23.2 12.2 50.9-7.4 46.4-33.7l-25-145.5 105.7-103c19-18.5 8.5-50.8-17.7-54.6L382 150.2 316.7 17.8c-11.7-23.6-45.6-23.9-57.4 0z")
              
            
!

CSS

              
                @use postcss-preset-env {
  features {
    nesting-rules: false;
    gap-properties: false;
    place-properties: false;
  }
}
@use postcss-nested;
@use postcss-simple-vars;

@import url("https://fonts.googleapis.com/css2?family=Manrope:wght@400;700&display=swap");

/* --- variables --- */

$animation-duration: .3s;
$animation-ease-out: cubic-bezier(.215, .61, .355, 1);

$font-weight-normal: 400;
$font-weight-bold: 700;

$outline-width: .25rem;
$outline-offset: .25em;

$blur-radius: 4px;

/* --- themes --- */

:root {
  --color-primary: #33a7d8;
  --color-primary-offset: #62d3ee;
  --text-primary: rgb(0 0 0 / 88%);
  --text-primary-inverted: rgb(255 255 255 / 88%);
  --text-secondary: rgb(0 0 0 / 56%);
  --bg: rgb(255 255 255);
  --bg-secondary: rgb(242 243 250);
  --bg-secondary-blur: rgb(242 243 250 / 88%); 
  --bg-dot: rgb(0 0 0 / 32%);
  --outline: rgb(51 216 144 / 88%);
  --shadow: rgb(0 0 0 / 8%);
  color-scheme: light;
}

:root.theme-dark {
  --color-primary: #33a7d8;
  --color-primary-offset: #62d3ee;
  --text-primary: rgb(255 255 255 / 88%);
  --text-primary-inverted: rgb(0 0 0 / 88%);
  --text-secondary: rgb(255 255 255 / 56%);
  --bg: rgb(10 10 10);
  --bg-secondary: rgb(25 25 25);
  --bg-secondary-blur: rgb(25 25 25 / 88%); 
  --bg-dot: rgb(255 255 255 / 32%);
  --outline: rgb(51 216 144 / 88%);
  --shadow: transparent;
  color-scheme: dark;
}

/* category colors */

:root {
  --green: #008000;
  --blue: #3455db;
  --red: #b22222;
  --purple: #b500b5;
  --gray: #4b6a88;
  --teal: #00869c;
}

/* --- base --- */

*,
*::before,
*::after {
  box-sizing: border-box;
}

:focus:not(:focus-visible) {
  outline: none;
}

:focus-visible {
  outline: $outline-width solid var(--outline);
  outline-offset: $outline-offset;
}

/* button reset */

button {
  padding: 0;
  margin: 0;
  border: none;
  color: inherit;
  font-family: inherit;
  background: none;
  cursor: pointer;
  appearance: button;
  user-select: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
}

[hidden] {
  display: none !important;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001s !important;
    transition-duration: 0.001s !important;
    animation-delay: 0s !important;
    animation-iteration-count: 1 !important;
  }
}

/* --- utilities --- */

.visually-hidden,
.visually-hidden-focusable:not(:focus):not(:focus-within) {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  border: 0 !important;
  overflow: hidden !important;
  white-space: nowrap !important;
  clip: rect(0, 0, 0, 0) !important;
}

/*--- page ---*/

.page {
  height: 100%;
  text-size-adjust: 100%;
}

body {
  display: grid;
  min-height: 100%;
  margin: 0;
  color: var(--text-primary);
  font-family: "Manrope", system-ui, sans-serif;
  background-color: var(--bg);
}

.page__body--offcanvas-open {
  height: 100%;
  overflow: hidden;
}

/* --- app --- */

.app {
  position: relative;
  width: 100%;
  min-width: 0;
  max-width: 25rem;
  height: 100%;
  margin: 0 auto;
  font-family: "Manrope", system-ui, sans-serif;
  background-color: var(--bg-secondary);

  &--offcanvas-open {
    height: 100%;
    overflow: hidden;
  }
}


.app__content {
  height: 100%;
  transition-property: border-radius, background-color, box-shadow, opacity, transform;
  transition-duration: $animation-duration;
  transition-timing-function: $animation-ease-out;
}

/* offcanvas */

.offcanvas {
  display: none;
  
  &.is-open {
    display: block;
  }
  
  &:not([aria-hidden="true"]) + .app__content {
    border-radius: 1rem;
    overflow: hidden;
    background-color: var(--bg);
    box-shadow: 0 .25rem 1rem var(--shadow);
    opacity: .64;
    transform: translateX(70%) scale(.88);
  }
}

.offcanvas__overlay {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 10;
  width: 100%;
  height: 100%;
  overflow: hidden;
}

.offcanvas__panel {
  width: 75%;
  height: 100%;
  animation-duration: $animation-duration;
  animation-timing-function: $animation-ease-out;
  animation-fill-mode: forwards;
  
  &.is-openning {
    animation-name: offcanvasOpen;
  }
  
  &.is-closing {
    animation-name: offcanvasClose;
  }
}

@keyframes offcanvasOpen {
  from {
    opacity: 0;
    transform: translateX(-100%);
  }
  
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes offcanvasClose {
  from {
    opacity: 1;
    transform: translateX(0);
  }
  
  to {
    opacity: 0;
    transform: translateX(-100%);
  }
}

/* --- sidepanel --- */

$sidepanel-padding: 3rem;

.sidepanel {
  display: grid;
  overflow-y: auto;
}

.sidepanel__container {
  position: relative;
  display: grid;
  grid-template:
    "logo logo" auto
    "menu menu" 1fr
    "user switcher" auto / 1fr auto;
  column-gap: 1rem;
  padding: $sidepanel-padding;
}

.sidepanel__logo {
  grid-area: logo;
  height: 6rem;
}

.sidepanel__menu {
  grid-area: menu;
  margin: 0 -$sidepanel-padding;
  align-self: center;
}

.sidepanel__user {
  grid-area: user;
}

.sidepanel__theme-switcher {
  grid-area: switcher;
  align-self: center;
}

.sidepanel__close-button {
  $inset: .5rem;
  
  position: absolute;
  bottom: $inset;
  left: $inset;
  width: calc(100% - ($inset * 2));
  padding: 1em;
  border: .125rem solid;
  font-size: 1rem;
  line-height: 1.5;
  font-family: inherit;
  background-color: var(--bg);
}

/* --- menu --- */

$menu-link-padding-h: $sidepanel-padding;

.menu__list {
  padding: 0;
  margin: 0;
  list-style: none;
}

.menu__link {
  display: block;
  padding: 1.5em $menu-link-padding-h;
  color: var(--text-secondary);
  font-size: 1.25rem;
  line-height: 1.5;
  font-weight: $font-weight-bold;
  text-decoration: none;
  animation: menuLinkSlideIn $animation-duration $animation-ease-out both;
  
  &--active {
    display: flex;
    align-items: center;
    color: var(--text-primary);
    
    &::before {
      $size: .25em;
      $gap: .5em;

      flex-shrink: 0;
      content: "";
      display: block;
      width: $size;
      height: $size;
      margin-right: $gap;
      margin-left: -$gap;
      border-radius: 50%;
      background-color: var(--color-primary);
    }
  }
}

.menu__item {
  
  &:nth-of-type(1) .menu__link {
    animation-delay: .08s;
  }
  
  &:nth-of-type(2) .menu__link {
    animation-delay: .12s;
  }

  &:nth-of-type(3) .menu__link {
    animation-delay: .16s;
  }

  &:nth-of-type(4) .menu__link {
    animation-delay: .20s;
  }
}

@keyframes menuLinkSlideIn {
  from {
    opacity: 0;
    transform: translateX(-5em);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* --- user --- */

.user {
  display: grid;
  grid-template:
    "image name"
    "image button" / auto 1fr;
  gap: .25em .75em;
  font-size: .875rem;
  line-height: 1.5;
}

.user__image {
  $size: 3em;

  grid-area: image;
  width: $size;
  height: $size;
  border-radius: 50%;
}

.user__name {
  grid-area: name;
  word-break: break-word;
}

.user__button {
  grid-area: button;
  justify-self: start;
  color: var(--color-primary);
  font-size: inherit;
  line-height: inherit;
}

/* --- theme toggle --- */

.theme-switcher { 
  $size: 2rem; 
  
  display: inline-grid;
  place-items: center;
  min-width: $size;
  min-height: $size;
  color: var(--text-primary);

  &--dark {
    
    .theme-switcher__icon-sun {
      display: none;
    }

    .theme-switcher__icon-moon {
      display: block;
    }
  }
}

.theme-switcher__icon {
  $size: 1.25rem;
  
  width: $size;
  height: $size;
  fill: currentColor;
}

.theme-switcher__icon-moon {
  display: none;
}

/* --- header --- */

$headerHeight: 3.5rem;

.header {
  display: grid;
  grid-template:
    "button-nav title button-search" / auto 1fr auto;
  column-gap: 1rem;
  align-items: center;
  min-height: $headerHeight;
}

.header__button {
  $size: $headerHeight;
  
  display: inline-grid;
  place-items: center;
  min-width: $size;
  min-height: $size;
}

.header__button-icon {
  $size: 1.25rem;
  
  width: $size;
  height: $size;
  fill: currentColor;
}

.header__button-nav {
  grid-area: button-nav;
}

.header__button-searh {
  grid-area: button-search;
}

.header__title {
  grid-area: title;
  font-weight: $font-weight-bold;
  font-size: 1.25rem;
  line-height: 1;
  text-align: center;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* --- burger --- */

$burgerLineGap: -.5rem;

.burger {
  display: flex;
  align-items: center;
  
  &--active {
    
    .burger__bar {
      transform: rotate(45deg);
      
      &::before {
        transform: rotate(-90deg) translateX($burgerLineGap);
      }

      &::after {
        opacity: 0;
      }
    }
  }
}

.burger__bar,
.burger__bar::before,
.burger__bar::after {
  display: block;
  width: 100%;
  height: .125rem;
  border-radius: .25rem;
  background-color: currentColor;
}

.burger__bar {
  position: relative;
  
  &::before,
  &::after {
    content: "";
    position: absolute;
  }
  
  &::before {
    top: $burgerLineGap;
  }
  
  &::after {
    bottom: $burgerLineGap;
  }
}

/* --- filter --- */

.filters {
  position: relative;
  min-width: 0;
  padding: 0;
  margin: 0;
  border: 0;
  transition-property: background-color, opacity, backdrop-filter;
  transition-duration: $animation-duration;
  transition-timing-function: $animation-ease-out;
  
  &::before,
  &::after {
    content: "";
    position: absolute;
    top: 0;
    z-index: 1;
    width: 1rem;
    height: 100%;
  }

  &::before {
    left: 0;
    background-image: linear-gradient(to left, rgb(255 255 255 / 0), var(--bg-secondary));
  }

  &::after {
    right: 0;
    background-image: linear-gradient(to right, rgb(255 255 255 / 0), var(--bg-secondary));
  }
  
  &--sticky {
    position: sticky;
    top: 0;
    z-index: 10;
    background-color: var(--bg-secondary-blur);
    opacity: 0;
    backdrop-filter: blur($blur-radius);
    transform: translateY(-100%);
    transition-property: opacity, transform;
    animation: filtersSlideDown $animation-duration $animation-ease-out;
  }
  
  &--sticky&--visible {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes filtersSlideDown {
  from {
    opacity: 0;
    transform: translateY(-100%);
  }
  
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.filters__wrapper {
  display: flex;
  overflow-x: auto;
}

.filters__container {
  flex-shrink: 0;
  display: flex; 
  column-gap: .5rem;
  padding: .75rem 1rem;
}

.filters__item {
  flex-shrink: 0;
  position: relative;
}

.filters__input {
  position: absolute;
  padding: 0;
  margin: 0;
  border: none;
  appearance: none;

  &:checked + .filters__button {
    color: var(--text-primary-inverted);
    background-image: linear-gradient(to right, var(--color-primary), var(--color-primary-offset));
  }

  &:focus-visible {
    outline: none;

    + .filters__button {
      outline: $outline-width dotted var(--outline);
      outline-offset: $outline-offset;
    }
  }
}

.filters__button {
  display: inline-flex;
  align-items: center;
  padding: .75em 1.25em;
  border-radius: .5em;
  color: var(--text-secondary);
  font-weight: $font-weight-bold;
  font-size: .875rem;
  line-height: 1;
  background-color: var(--bg);
  box-shadow: 0 .125rem .75rem var(--shadow);
  cursor: pointer;
  user-select: none;

  &--has-icon {
    column-gap: .5em;
  }
}

.filters__button-icon {
  $size: 1em;

  width: $size;
  height: $size;
  fill: currentColor;
}

/* --- schedule --- */

.schedule {
  $padding: .5rem;

  padding-right: $padding;
  padding-bottom: $padding;
}

/* --- section day --- */

.section-day__title {
  position: sticky;
  top: 0;
  z-index: 1;
  padding: 1rem .5rem;
  margin: 0;
  color: var(--text-secondary);
  font-weight: $font-weight-normal;
  font-size: .875rem;
  text-align: center;
}

.section-day__title-text {
  display: inline-block;
  padding: .25em .5em;
  border-radius: 1em;
  background-color: var(--bg-secondary-blur);
  backdrop-filter: blur($blur-radius);
}

.section-day__content {
  display: grid;
  row-gap: .5rem;
}

/* --- section period --- */

.section-period {
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: 1rem;
}

.section-period__events {
  display: grid;
  grid-row-gap: .5rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

/* --- period time --- */

$periodFontSize: 1rem;
$periodDotSize: 1.5px;
$periodDotGap: 16px;
$periodDotPosition: calc($periodDotGap / 2 + $periodDotSize);

.period-time {
  --period-dot-color: var(--bg-dot);
  display: flex;
  padding: .75rem 0 .75rem .25rem;
  margin: 0;
  font-weight: 400;
  font-size: $periodFontSize;
  line-height: 1;
  
  &::before {
    content: "";
    display: block;
    width: calc($periodDotSize * 2);
    background-image: radial-gradient(var(--period-dot-color) $periodDotSize, rgb(0 0 0 / 0) $periodDotSize);
    background-position: $periodDotPosition $periodDotPosition;
    background-size: $periodDotGap $periodDotGap;
  }
  
  &--completed {
    --period-color: var(--text-secondary);
  }
  
  &--active {
    --period-color: var(--color-primary);
    --period-dot-color: var(--color-primary);
  }
  
  &--coming {
    --period-color: var(--text-primary);
  }
}

.period-time__text {
  position: sticky;
  top: 1rem;
  align-self: flex-start;
  display: grid;
  grid-template-areas:
    "line start"
    "line end";
  gap: .75em .5em;
  margin-top: calc(($periodFontSize / 2) + $periodDotSize);
  margin-left: calc($periodDotSize * -2);
  color: var(--period-color);
  font-size: 1rem;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  
  &::before {
    $height: $periodDotSize * 2;
    
    content: "";
    grid-area: line;
    width: 1rem;
    height: calc($height);
    margin-top: calc(($periodFontSize - ($height)) / 2);
    border-radius: $periodFontSize;
    background-color: currentColor;
  }
}

.period-time__start,
.period-time__end {
  min-width: 5ch;
}

.period-time__start {
  grid-area: start;
  font-weight: 600;
}

.period-time__end {
  font-size: .875em;
  grid-area: end;
  color: var(--text-secondary);
}

/* --- event --- */

.event {
  position: relative;
  display: grid;
  grid-template-areas:
    "meta   meta"
    "title  title"
    "author button";
  grid-template-columns: 1fr auto;
  gap: .5rem;
  padding: 1rem;
  border-radius: .5rem;
  background-color: var(--bg);
  box-shadow: 0 .125rem 1.5rem var(--shadow);
  
  &--activity {
    $bg-size: 8rem;
    
    grid-template-areas:
      "meta  meta"
      "title button";
    background-repeat: no-repeat;
    background-position: right -15% bottom 75%;
    background-size: $bg-size $bg-size;
  }
  
  &--background-1 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 113 103'><circle cx='64.5' cy='48.5' r='48.5' fill='%23ff5edd' opacity='.24'/><circle cx='24.5' cy='78' r='24.5' fill='%235e99ff' opacity='.12'/></svg>");
  }
  
  &--background-2 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 126 158'><path d='M81 37l45 77-77 44L5 81z' fill='%23ffef5e' opacity='.12'/><path d='M30 1l6 3L6 55l-6-3z' fill='%23feb0a5' opacity='.24'/><ellipse cx='39.9' cy='43.5' rx='12.5' ry='12' fill='%23a698fc' opacity='.32'/></svg>");
  }
  
  &--background-3 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 127 161'><path d='M82 41l44 76-76 44L6 85z' fill='%23cb7ef9' opacity='.12'/><path d='M43 1l52 52-42 42L1 43z' fill='%23feb0a5' opacity='.24'/></svg>");
  }
  
  &--background-4 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 134 162'><ellipse cx='72.6' cy='107' rx='54.5' ry='55' fill='%23ff5edd' opacity='.12'/><ellipse cx='92.6' cy='42' rx='41.5' ry='42' fill='%23cb7ef9' opacity='.24'/><path d='M0 73l28-16 16 28-28 16z' fill='%2398fcc1' opacity='.32'/></svg>");
  }
  
  &--background-5 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 115 115'><path d='M1 91l24-14 14 24-24 14z' fill='%23ffef5e' opacity='.24'/><path d='M17 39l41 11-11 41L6 80z' fill='%23ff625e' opacity='.24'/><path d='M70 1l45 45-45 45-45-45z' fill='%235effae' opacity='.32'/></svg>");
  }
  
  &--background-6 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 142 168'><path d='M31 51l69 47L0 121z' fill='%23cb7ef9' opacity='.12'/><path d='M127 24l15 81-87-55z' fill='%23ff5edd' opacity='.24'/><path d='M122 109l15 81-87-55z' fill='%235e99ff' opacity='.32'/></svg>");
  }
  
  &--background-7 {
    background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 144 95'><path d='M88 39l12 60L8 28 151 6z' fill='%235e99ff' opacity='.12'/><path d='M54 86l-4-4 70-71 5 4z' fill='%23ffef5e' opacity='.24'/></svg>");
  }
}

.event__meta {
  grid-area: meta;
}

.event__title {
  grid-area: title;
  font-size: 1rem;
  line-height: 1.5;
  font-weight: $font-weight-bold;
  word-break: break-word;
}

.event__link {
  color: var(--text-primary);
  text-decoration: none;
  
   &::before {
    content: "";
    position: absolute;
    inset: 0;
  }
}

.event__author {
  grid-area: author;
}

.event__favorite-button {
  z-index: 1;
  grid-area: button;
  align-self: end;
}

/* --- meta --- */

.meta {
  display: flex;
  flex-wrap: wrap;
  column-gap: .3em;
  color: var(--text-secondary);
  font-size: .875rem;
  line-height: 1.5;
  word-break: break-word;
}

/* --- author --- */

.author {
  display: grid;
  grid-template:
    "image name"
    "image company" / auto 1fr;
  gap: .125em .75em;
  align-items: center;
  font-size: .875rem;
  line-height: 1.5;
}

.author__image {
  $size: 3em;
  
  grid-area: image;
  width: $size;
  height: $size;
  border-radius: 50%;
}

.author__name {
  grid-area: name;
  word-wrap: break-word;
}

.author__company {
  grid-area: company;
  color: var(--text-secondary);
  word-wrap: break-word;
}

/* --- category --- */

.category {
  
  &--2 {
    color: var(--green);
  }

  &--3 {
    color: var(--blue);
  }

  &--4 {
    color: var(--red);
  }

  &--5 {
    color: var(--purple);
  }

  &--6 {
    color: var(--gray);
  }

  &--7 {
    color: var(--teal);
  }
}

/* --- favorite button --- */

.favorite-button {
  $size: 1.5rem;
  
  position: relative;
  display: grid;
  place-items: center;
  min-width: $size;
  min-height: $size;

  /* increase clickable zone */
  &::before {
    $size: 2.5rem;

    content: "";
    position: absolute;
    width: $size;
    height: $size;
  }
  
  &--active {
    
    .favorite-button__icon-stroke {
      display: none;
    }
    
    .favorite-button__icon-filled {
      display: block;
    }
  }

  &--active&--init {

    .favorite-button__icon {
      animation: scaleUp $animation-duration $animation-ease-out;
    }
  }
}

@keyframes scaleUp {
  50% {
    transform: scale(1.25);
  }
}

.favorite-button__icon {
  $size: 1.25rem;
  
  width: $size;
  height: $size;
  fill: currentColor;
}

.favorite-button__icon-filled {
  display: none;
}
              
            
!

JS

              
                function offcanvasAnimation(type, modal, trigger, className, animationName) {
  const body = document.body;
  const app = document.querySelector('.app');
  const panel = modal.querySelector('.sidepanel');
  const burger = trigger.querySelector('.burger');
  
  if (type == 'open') {
    body.classList.add('page__body--offcanvas-open');
    app.classList.add('app--offcanvas-open');
  }

  panel.classList.add(className);
  burger.classList.toggle('burger--active');
  panel.onanimationend = (event) => {
    if (event.animationName == animationName) {
      panel.classList.remove(className);
      if (type == 'close') {
        body.classList.remove('page__body--offcanvas-open');
        app.classList.remove('app--offcanvas-open');
      }
    }
  }
}

// offcanvas
MicroModal.init({
  onShow: (modal, trigger) => (offcanvasAnimation('open', modal, trigger, 'is-openning', 'offcanvasOpen')),
  onClose: (modal, trigger) => (offcanvasAnimation('close', modal, trigger, 'is-closing', 'offcanvasClose')),
  awaitCloseAnimation: true
});

// show filters on scroll up
window.addEventListener('DOMContentLoaded', () => {
  const content = document.querySelector('.js-app-content');
  const filters = document.querySelector('.filters');
  let filtersTop = filters.offsetTop;
  let filtersBottom = filters.offsetTop + filters.offsetHeight;
  let scrollPosPrev = 0;
  
  window.onscroll = () => {
    let scrollPosCur = window.scrollY;
    if (scrollPosCur > filtersBottom) {
      if (scrollPosCur < scrollPosPrev) {
        filters.classList.add('filters--sticky', 'filters--visible');
      } else {
        filters.classList.remove('filters--visible');
      }
    }
    if (scrollPosCur < filtersTop) {
      filters.classList.remove('filters--sticky', 'filters--visible');
    }
    scrollPosPrev = scrollPosCur;
  } 
});

// filter
window.addEventListener('DOMContentLoaded', () => {
  const filters = document.querySelectorAll('.js-filter');
  const events = document.querySelectorAll('.event');
  const periods = document.querySelectorAll('.section-period');
  const days = document.querySelectorAll('.section-day');
  
  function hideSections(elements) {
    elements.forEach(element => {
      let shownevents = element.querySelectorAll('.event:not([hidden])').length;
      if (shownevents == 0) {
        element.hidden = true;
      } else {
        element.hidden = false;
      }
    })
  }
  
  filters.forEach(filter => {
    const value = filter.value;
    filter.onchange = () => {
      events.forEach(event => {
        switch (value) {
          case '':
            event.hidden = false;
            break;
          case 'favorites':
            if (event.dataset.hasOwnProperty('favorite'))
              event.hidden = false;
            else
              event.hidden = true;
            break;
          case 'live':
            if (event.dataset.hasOwnProperty('live'))
              event.hidden = false;
            else
              event.hidden = true;
            break;
          default:
            let filterData = event.dataset.filter;
            if (!filterData || filterData !== value)
              event.hidden = true;
            else
              event.hidden = false;
        }
      })
      hideSections(periods);
      hideSections(days);
    }
  })
 });

// favorite button
(() => {
  const favoriteButtons = document.querySelectorAll('.favorite-button');
  const isAddedAttribute = 'data-favorite';
  
  favoriteButtons.forEach(button => {
    const event = button.closest('.event');
    const eventTitle = event.querySelector('.event__title');
    const eventTitleText = eventTitle.textContent;
    
    button.onclick = () => {
      button.classList.add('favorite-button--init'); // allows animation for active state
      button.classList.toggle('favorite-button--active');
      event.toggleAttribute(isAddedAttribute);
      button.setAttribute(
        'aria-label',
        event.hasAttribute(isAddedAttribute) ?
          `Remove "${eventTitleText}" from favorites` : `Add "${eventTitleText}" to favorites`
      );
    }
  })
})();

// theme switcher
(() => {
  const themeButton = document.querySelector('.theme-switcher');
  const defaultTheme = 'light';
  const darkTheme = 'dark';
  let currentTheme = defaultTheme;

  themeButton.onclick = () => {
    if (currentTheme == defaultTheme)
      currentTheme = darkTheme
    else
      currentTheme = defaultTheme
    document.documentElement.classList.toggle('theme-dark');
    themeButton.classList.toggle('theme-switcher--dark');
    themeButton.setAttribute(
      'aria-label',
      `Switch to ${currentTheme} theme`
    );
  }
})();
              
            
!
999px

Console