<div class="layout">
  <div class="layout__backdrop"></div>
  <div class="layout__frontdrop"></div>
  <div class="layout__wrapper">
    <header class="layout__header">
      <nav>
        <ul class="nav nav--header nav--header-1">
          <li class="nav__item nav__item--home">
            <a class="nav__link" href="#0">Home</a>
          </li>
          <li class="nav__item nav__item--about">
            <a class="nav__link" href="#0">About</a>
          </li>
          <li class="nav__item nav__item--clients">
            <a class="nav__link" href="#0">Clients</a>
            <ul class="nav nav--header nav--header-2">
              <li class="nav__item">
                <a class="nav__link" href="#0">Burger King</a>
              </li>
              <li class="nav__item">
                <a class="nav__link" href="#0">Southwest Airlines</a>
              </li>
              <li class="nav__item">
                <a class="nav__link"  href="#0">Levi Strauss</a>
              </li>
            </ul>
          </li>
          <li class="nav__item nav__item--services">
            <a class="nav__link" href="#0">Services</a>
            <ul class="nav nav--header nav--header-2">
              <li class="nav__item">
                <a class="nav__link" href="#0">Print Design</a>
              </li>
              <li class="nav__item">
                <a class="nav__link" href="#0">Web Design</a>
              </li>
              <li class="nav__item">
                <a class="nav__link" href="#0">Mobile App Development</a>
              </li>
            </ul>
          </li>
          <li class="nav__item nav__item--contact">
            <a class="nav__link" href="#0">Contact</a>
          </li>
        </ul>
      </nav>
    </header>
    <main class="layout__main">
      <section class='hero'>
        <div class="hero-block hero-block--header">
          <h1 class="hero-title">
            Fork It <em>Navigation with Sub-navigation, a Codepen Challenge, Aug 2019.</em>
            
          </h1>
          <p class="hero-text">The idea was to fork <a href="https://codepen.io/pen?template=PMbwKb" target="_blank">a pretty basic navigation</a> and make something nice with it. The content inspired me some kind of advertising adgency with a bold navigation and a little content. Made me work on my hover and active state more than what I'm used to in those weekly challenges.</p>
        </div>
      </section>
    </main>
  </div>
</div>

* {
  box-sizing: border-box;
}

html,
body {
  --ccft-cs-background: #000;
  --ccft-cs-on-surface: #fff;
  --ccft-cs-surface: #fff;
  --ccft-cs-primary: hsl(14, 97%, 65%);
  --ccft-cs-primary-alt: hsla(14, 97%, 65%, .3);
  --ccft-ts-primary: Montserrat, sans-serif;
  --ccft-ts-secondary: 'Abril Fatface', serif;
  --ccft-spacer-x: 40px;
  --ccft-spacer-y: 40px;
  --ccft-brand-size: 60px;
  
  background-color: var(--ccft-cs-background);
  font-family: var(--ccft-ts-primary);
  margin: 0;
}

.layout {
  background-image: url(https://source.unsplash.com/rf5R1qXwlDU/1600x900);
  background-position: 0 0;
  background-size: cover;
  height: 100vh;
  overflow: hidden;
  position: relative;
}

.layout.nav--active main {
  opacity: .2;
  user-select: none;
}

.layout__backdrop,
.layout__frontdrop {
  background-color: rgba(0, 0, 0, .3);
  content: '';
  display: block;
  height: 100%;
  left: 0;
  position: fixed;
  transform-origin: 0% 50%;
  width: 100%;
  z-index: 0;
}

.layout__backdrop {
  transform: scaleX(.34) translateX(calc(67% * 3));
}

.layout.nav--active .layout__frontdrop {
  background-color: var(--ccft-cs-primary-alt);
  visibility: visible;
}

.layout__frontdrop {
  opacity: 0;
  visibility: hidden;
  z-index: 2;
}

.layout__wrapper {
  display: grid;
  grid-template-columns: 300px repeat(3, 1fr);
  margin: auto;
  height: 100%;
}

.layout__main {
  transition: opacity .3s;
  z-index: 1;
}

.hero {
  padding-top: 10rem;
}

.hero-title {
  color: #fff;
  font-family: var(--ccft-ts-secondary);
  font-weight: 400;
  font-size: 4.75rem;
  line-height: 1.2;
  margin-left: auto;
  margin-right: 5rem;
  margin-bottom: 0;
  position: relative;
  width: 32.5rem;
  z-index: 1;
}

.hero-title em {
  display: block;
  font-size: 2rem;
  font-style: normal;
  line-height: 1.2;
  transform: translateX(2.5rem);
}

.hero-text {
  background-color: rgba(0, 0, 0, .3);
  color: #fff;
  font-size: .92rem;
  line-height: 1.75;
  margin: 0;
  margin-left: auto;
  margin-right: 6rem;
  padding: 5rem 3rem 3rem;
  transform: translateY(-3rem);
  width: 50%;
  z-index: 0;
}

.hero-text a {
  box-shadow: 0 4px #fff;
  color: #fff;
  text-decoration: none;
}

.hero-block--content > *:last-child {
  margin-bottom: 0;
}

.layout__main {
  display: flex;
  flex-direction: column;
}

.layout__header {
  height: 100%;
  z-index: 2;
}

.layout__header nav {
  height: 100%;
}

.layout__main {
  grid-column: span 3;
}

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

.nav--header-1 {
  counter-reset: n;
  height: 100%;
  padding: 0 2rem;
  position: relative;
}

.nav--header-1 > .nav__item:not(.nav__item--home) {
  counter-increment: n;
}

.nav--header-1 > .nav__item:not(.nav__item--home) > .nav__link {
  color: var(--ccft-cs-on-surface);
  display: block;
  font-family: var(--ccft-ts-secondary);
  font-size: 1.75rem;
  line-height: 1;
  letter-spacing: .045em;
  padding: 1rem 1rem;
  padding-left: 3rem;
  padding-top: 3rem;
  position: relative;
  overflow: hidden;
  text-decoration: none;
  transition: transform .2s;
  transition-timing-function: cubic-bezier(0.2, 1, 0.3, 1);
  z-index: 1;
}

.nav--header-1 > .nav__item > .nav__link::before {
  content: counter(n, decimal-leading-zero);
  display: block;
  font-family: var(--ccft-ts-primary);
  font-size: 6rem;
  font-weight: bold;
  left: 0;
  top: 0;
  opacity: .25;
  position: absolute;
  transition: transform .2s;
  z-index: -1;
}

.nav--header-1 > .nav__item > .nav__link:hover,
.nav--header-1 > .nav__item.nav__item--active > .nav__link {
  color: var(--ccft-cs-primary);
  transform: translateX(.5rem);
}

.nav--header-1 > .nav__item.nav__item--active .nav--header-2 {
  visibility: visible;
}

.nav--header-1 .nav__item--home {
  background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M14.145 8.633l-2.145-8.633-2.148 8.636c-.572.366-1.034.877-1.358 1.477l-8.494 1.887 8.494 1.887c.324.6.786 1.111 1.358 1.477l2.148 8.636 2.157-8.64c.571-.367 1.03-.879 1.353-1.479l8.49-1.881-8.492-1.884c-.324-.603-.788-1.116-1.363-1.483zm-2.145 5.367c-1.104 0-2-.896-2-2s.896-2 2-2 2 .896 2 2-.896 2-2 2zm7 5l-3.43-2.186c.474-.352.893-.771 1.245-1.245l2.185 3.431zm-3.521-11.882l3.521-2.117-2.119 3.519c-.386-.542-.86-1.015-1.402-1.402zm-6.955 9.767l-3.524 2.115 2.118-3.521c.387.543.862 1.018 1.406 1.406zm-1.34-8.453l-2.184-3.431 3.431 2.184c-.474.352-.894.772-1.247 1.247z" fill="rgb(255, 255, 255)" style="transform-origin: 50% 50%; transform: rotateZ(-27deg);"/></svg>');
  background-position: 0px 50%;
  background-repeat: no-repeat;
  background-size: var(--ccft-brand-size) var(--ccft-brand-size);
  margin-bottom: 60px;
  padding: 0;
}

.nav--header-1 .nav__item--home > .nav__link {
  display: block; /* Necessary for text-indent to work */
  height: calc(var(--ccft-brand-size) + 40px);
  text-indent: -999px;
}

.nav--header-2 {
  height: 100%;
  left: 270px;
  opacity: 0;
  padding: 2.5rem 5rem;
  position: fixed;
  top: 0;
  visibility: hidden;
  width: 100%;
}

.nav--header-2::before {
  background-image: url('data:image/svg+xml;utf8,<svg width="24" height="24" xmlns="http://www.w3.org/2000/svg" fill-rule="evenodd" clip-rule="evenodd"><path d="M23.954 21.03l-9.184-9.095 9.092-9.174-2.832-2.807-9.09 9.179-9.176-9.088-2.81 2.81 9.186 9.105-9.095 9.184 2.81 2.81 9.112-9.192 9.18 9.1z" fill="rgb(255, 255, 255)"/></svg>');
  background-repeat: no-repeat;
  background-size: 30px 30px;
  content: '';
  cursor: pointer;
  display: block;
  margin-bottom: 6rem;
  height: 30px;
  width: 30px;
}

.nav--header-2 > .nav__item {
  margin-bottom: 2.75rem;
}

.nav--header-2 > .nav__item > .nav__link {
  background-image: linear-gradient(to bottom, var(--ccft-cs-primary) 0%, var(--ccft-cs-primary) 100%);
  background-position: 0 100%;
  background-repeat: repeat-x;
  background-size: 6px 6px;
  color: #fff;
  font-family: var(--ccft-ts-primary);
  font-size: 2.75rem;
  font-weight: bold;
  letter-spacing: .05em;
  text-decoration: none;
  transition: background-size .25s, color .3s;
}

.nav--header-2 > .nav__item > .nav__link:hover {
  background-size: 6px 50px;
  color: #000000;
}

const items = document.querySelectorAll('.nav--header-1 > .nav__item');
const rootElement = document.querySelector('.layout');

const colors = [
  'hsla(14, 97%, 65%, 0.4)',
];

// Local state.
const state = {
  navigationItems: {},
  root: rootElement,
};

for (let navItemIndex = 0; navItemIndex < items.length; ++navItemIndex) {
  const stateItem = {
    color: colors[navItemIndex % colors.length],
    element: items[navItemIndex],
    id: navItemIndex,
    isActive: false,
    type: 'DEFAULT',
  } 
  
  const subNav =  items[navItemIndex].querySelector('.nav');
  if (subNav) {
    // current element has a subNav.
    stateItem.childNavigation = subNav;
    stateItem.type = 'PARENT';
  }
  
  stateItem.onClick = (event) => {
    const actualOnClick = () => {
      if (state.activeItem === navItemIndex) {
        return;
      }
      
      if (state.activeItem) {
        state.activeItem = null;
      } 

      if ('PARENT' === state.navigationItems[navItemIndex].type) {
        // Set new active item.
        state.activeItem = navItemIndex;

        animateShow(state);
      }
    };
    
    if (state.activeItem) {
      return animateHide(state, actualOnClick);
    }
    
    return actualOnClick();
  };
  
  // Add this item to the state.
  state.navigationItems[navItemIndex] = stateItem;
}

const animateShow = (state) => {
  const animation = anime.timeline();
  console.log(state.navigationItems[state.activeItem]);
  
  animation.add({
    backgroundColor: state.navigationItems[state.activeItem].color,
    begin: () => {
      state.root.classList.add('nav--active');
    },
    complete: () => {
      state.navigationItems[state.activeItem].element.classList.add('nav__item--active');
    },
    duration: 450,
    easing: 'easeOutExpo',
    opacity: 1,
    translateX: [
      {delay: 300, value: '270px',},
    ],
    scaleX: [
      {value: 0},
      {value: 1},
    ],
    targets: '.layout__frontdrop',
  })
  .add({
    duration: 70,
    opacity: [0, 1],
    targets: state.navigationItems[state.activeItem].childNavigation,
  }).add({
    delay: anime.stagger(70),
    opacity: [0, 1],
    translateY: ['100%', '0'],
    targets: state.navigationItems[state.activeItem].childNavigation.querySelectorAll('.nav__item'),
  });
  
  return animation;
};

const animateHide = (state, complete) => {
  const animation = anime.timeline({
    complete: complete,
  });
  
  animation.add({
    duration: 210,
    opacity: [1, 0],
    translateY: [0, '+=50px'],
    targets: state.navigationItems[state.activeItem].childNavigation,
  }).add({
    complete: () => {
      // Clean-up current active item.
      state.root.classList.remove('nav--active');
      state
        .navigationItems[state.activeItem]
        .element
        .classList
        .remove('nav__item--active')
      ;
    },
    duration: 250,
    easing: 'easeOutCirc',
    scaleX: [
      {value: 0,},
    ],
    translateX: [
      {value: 0},
    ],
    targets: '.layout__frontdrop',
  });
  
  return animation;
};

(() => {
  // Ready to fight.
  const introAnimation = anime.timeline({
    complete: () => {
      for (let stateItemIndex = 0; stateItemIndex < Object.values(state.navigationItems).length; ++ stateItemIndex) {
        state.navigationItems[stateItemIndex].element.addEventListener(
          'click',
          state.navigationItems[stateItemIndex].onClick
        );
        
        // Reset transform to prevent the implicit z-index / position relative to trigger.
        state.navigationItems[stateItemIndex].element.style.transform = '';
      }
    },
  });

  introAnimation.add({
    duration: 350,
    delay: 1000,
    easing: 'easeOutCirc',
    targets: '.layout__backdrop',
    scaleX: [0, 1],
  }).add({
    delay: anime.stagger(75),
    duration: 450,
    easing: 'easeOutCirc',
    opacity: [0, 1],
    translateY: ['100%', '0%'],
    targets: '.nav--header-1 > .nav__item:not(.nav__item--home)',
  }).add({
    easing: 'easeOutExpo',
    targets: '.layout__backdrop',
    translateX: [
      {delay: 350, value: (67) + '%'},
    ],
  }).add({
    duration: 350,
    easing: 'easeOutExpo',
    targets: '.hero-title',
    opacity: [0, 1],
    translateY: ['50px', '0'],
  }).add({
    duration: 350,
    easing: 'easeOutExpo',
    targets: '.hero-text',
    opacity: [0, 1],
    translateY: ['0', '-3rem'],
  }, '-=100');
})();