<nav>
  <div class="toggle">
    <input type="checkbox">
    <span class="btn"></span>
    <ul>
      <li><a href=""><i class="fa fa-vimeo"></i></a></li>
      <li><a href=""><i class="fa fa-instagram"></i></a></li>
      <li><a href=""><i class="fa fa-facebook"></i></a></li>
      <li><a href=""><i class="fa fa-twitter"></i></a></li>
      <li><a href="https://github.com/fussinatto" target="_blank"><i class="fa fa-github"></i></a></li>
      <li><a href="https://codepen.io/fussinatto/" target="_blank"><i class="fa fa-codepen"></i></a></li>
    </ul>
  </div>
</nav>

html,
body {
    text-align: center;
    background-color: #273559;     
}

nav {
    position: absolute;
    width: 120px;
    height: 120px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);

    .toggle {
        height: 100%;
        width: 100%;

    }

    input[type="checkbox"] {
        opacity: 0;
        position: absolute;
        cursor: pointer;
        z-index: 1;
        height: 100%;
        width: 100%;
        left: 0;
        top: 0;
        z-index: 10;


        &:checked {
            ~ .btn {
              &:after,
            &:before {
                  //transform: rotate(225deg);
              }
            }

            ~ ul li {
                @for $i from 1 through 6 {
                    &:nth-child(#{$i}) {
                        transform: rotate($i*60deg) translate(6em) rotate(-$i*60deg);
                    }
                }
            }
        }

        &:hover {
      ~ .btn {
        background-color: #1782CC;
        }
        }
    }
    .btn {
        display: block;
        width: 100%;
        height: 100%;
        position: relative;
        background-color: #1DA2FF;
        border-radius: 50%;
        cursor: pointer;
        transition: transform 1.25s cubic-bezier(.8, 0, .2, 1), background-color 0.25s;
        z-index: 9;
    box-shadow: 0 5px 25px -4px rgba(0,0,0,0.5), inset 0 -3px 4px -1px rgba(0,0,0,0.2), 0 -5px 15px -1px rgba(104,193,255,0.4), inset 0 3px 4px -1px rgba(255,255,255,0.2);


        &:after,
        &:before {
            content: '';
            position: absolute;
            background-color: #FFF;
            border-radius: 4px;
            transition: transform 1.25s cubic-bezier(.8, 0, .2, 1);
        }

         &:after {
          width: 40px;
            height: 8px;
            top: 56px;
            left: 40px;
         }
        &:before {
            width: 8px;
            height: 40px;
            top: 40px;
            left: 56px;
        }
    }
    ul {
        position: absolute;
        top: 50%;
        left: 50%;
    }
    li {
        transition: transform 1.25s cubic-bezier(.7, 0, .3, 1);

        a {
            position: absolute;
            width: 40px;
            height: 40px;
            line-height: 42px;
            background-color: #1DA2FF;
            border-radius: 50%;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            transition: background-color 0.5s;

            .fa {
        color: #fff;
      }

      &:hover {
        background-color: #FF590D;
      }
        }
    }
}