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HTML 

              
                <nav class="menu">
  <ol>
    <li class="menu-item"><a href="#0">Home</a></li>
    <li class="menu-item"><a href="#0">About</a></li>
    <li class="menu-item">
      <a href="#0">Widgets</a>
      <ol class="sub-menu">
        <li class="menu-item"><a href="#0">Big Widgets</a></li>
        <li class="menu-item"><a href="#0">Bigger Widgets</a></li>
        <li class="menu-item"><a href="#0">Huge Widgets</a></li>
      </ol>
    </li>
    <li class="menu-item">
      <a href="#0">Kabobs</a>
      <ol class="sub-menu">
        <li class="menu-item"><a href="#0">Shishkabobs</a></li>
        <li class="menu-item"><a href="#0">BBQ kabobs</a></li>
        <li class="menu-item"><a href="#0">Summer kabobs</a></li>
      </ol>
    </li>
    <li class="menu-item"><a href="#0">Contact</a></li>
  </ol>
</nav>
!

CSS 

              
                $black: #2A363B
$red: #F67280
$red-dark: #C06C84
$orange: #F8B195
$yellow: #FECEAB
$white: #FFF

@mixin mobile
  @media screen and (max-width: 600px)
    @content

.menu
  background: $red
  height: 4rem
  
  ol
    list-style-type: none
    margin: 0 auto
    padding: 0
    
  > ol
    max-width: 1000px
    padding: 0 2rem
    display: flex
    
    > .menu-item
      flex: 1
      padding: 0.75rem 0
      
      &:after
        content: ''
        position: absolute
        width: 4px
        height: 4px
        border-radius: 50%
        bottom: 5px
        left: calc(50% - 2px)
        background: $yellow
        will-change: transform
        transform: scale(0)
        transition: transform 0.2s ease
      
      &:hover:after
        transform: scale(1)
  
  &-item
    position: relative
    line-height: 2.5rem
    text-align: center
    
    a
      overflow: hidden
      white-space: nowrap
      text-overflow: ellipsis
      display: block
      color: $white
    
    @at-root .sub-menu &
      padding: 0.75rem 0
      background: $red
      opacity: 0
      transform-origin: bottom
      animation: enter 0.2s ease forwards
      
      @for $n from 1 through 3
        &:nth-child(#{$n})
          animation-duration: 0.2s + 0.1s * ($n - 1)
          animation-delay: 0.1s * ($n - 1)
      
      &:hover
        background: $orange
      
      a
        padding: 0 0.75rem
        
      @include mobile
        background: $red-dark

  @include mobile
    position: relative
    
    &:after
      content: ''
      position: absolute
      top: calc(50% - 2px)
      right: 1rem
      width: 30px
      height: 4px
      background: $white
      box-shadow: 0 10px $white, 0 -10px $white
      
    > ol
      display: none
      background: $red
      flex-direction: column
      justify-content: center
      height: 100vh
      animation: fade 0.2s ease-out
      
      > .menu-item
        flex: 0
        opacity: 0
        animation: enter 0.3s ease-out forwards
        
        @for $n from 1 through 5
          &:nth-child(#{$n})
            animation-delay: 0.1s * ($n - 1)
        
        & + .menu-item
          margin-top: 0.75rem
          
        &:after
          left: auto
          right: 1rem
          bottom: calc(50% - 2px)
        
        &:hover
          z-index: 1
      
    &:hover
      > ol
        display: flex
      
      &:after
        box-shadow: none
      
.sub-menu
  position: absolute
  width: 100%
  top: 100%
  left: 0
  display: none
  z-index: 1
  
  @at-root .menu-item:hover > &
    display: block
    
  @include mobile
    width: 100vw
    left: -2rem
    top: 50%
    transform: translateY(-50%)
  
html, body
  font-size: 16px
  font-family: 'Fira Mono', monospace
  margin: 0
  background: $black
 
*
  box-sizing: border-box

  &:before, &:after
    box-sizing: inherit

a
  text-decoration: none
  
@keyframes enter
  from
    opacity: 0
    transform: scaleY(0.98) translateY(10px)
  to
    opacity: 1
    transform: none
    
@keyframes fade
  from
    opacity: 0
  to
    opacity: 1
!

JS 

              
                /*
  No JS - be sure to check out the mobile menu >|
*/
!
999px

Console