/* NAVIGATION */
nav ul li a,
nav ul li a:after,
nav ul li a:before {
  transition: all .5s;
}
nav ul li a:hover {
  color: #555;
}

/* stroke */
nav.stroke ul li a,
nav.fill ul li a {
  position: relative;
}
nav.stroke ul li a:after,
nav.fill ul li a:after {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
  width: 0%;
  content: '.';
  color: transparent;
  background: #aaa;
  height: 2px;
}
nav.stroke ul li a:hover:after {
  width: 100%;
}

nav.fill ul li a {
  transition: all 2s;
}

nav.fill ul li a:after {
  text-align: left;
  content: '.';
  margin: 0;
  opacity: 0;
}
nav.fill ul li a:hover {
  color: #fff;
  z-index: 1;
}
nav.fill ul li a:hover:after {
  z-index: -10;
  animation: fill 1s forwards;
  -webkit-animation: fill 1s forwards;
  -moz-animation: fill 1s forwards;
  opacity: 1;
}

/* Circle */
nav.circle ul li a {
  position: relative;
  overflow: hidden;
  z-index: 1;
}
nav.circle ul li a:after {
  display: block;
  position: absolute;
  margin: 0;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  content: '.';
  color: transparent;
  width: 1px;
  height: 1px;
  border-radius: 50%;
  background: transparent;
}
nav.circle ul li a:hover:after {
  -webkit-animation: circle 1.5s ease-in forwards;
}

/* SHIFT */
nav.shift ul li a {
  position:relative;
  z-index: 1;
}
nav.shift ul li a:hover {
  color: #91640F;
}
nav.shift ul li a:after {
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  margin: auto;
  width: 100%;
  height: 1px;
  content: '.';
  color: transparent;
  background: #F1C40F;
  visibility: none;
  opacity: 0;
  z-index: -1;
}
nav.shift ul li a:hover:after {
  opacity: 1;
  visibility: visible;
  height: 100%;
}

/* Keyframes */
@-webkit-keyframes fill {
  0% {
    width: 0%;
    height: 1px;
  }
  50% {
    width: 100%;
    height: 1px;
  }
  100% {
    width: 100%;
    height: 100%;
    background: #333;
  }
}

/* Keyframes */
@-webkit-keyframes circle {
  0% {
    width: 1px;
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
    margin: auto;
    height: 1px;
    z-index: -1;
    background: #eee;
    border-radius: 100%;
  }
  100% {
    background: #aaa;
    height: 5000%;
    width: 5000%;
    z-index: -1;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    margin: auto;
    border-radius: 0;
  }
}