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                <nav id="main-nav">
    <li><a href="#">About Us</a></li>
    <li><a href="#">Product List</a></li>
    <li class="last"><a href="#">Contact</a></li>
    <li class="last"><a href="#">FAQ</a></li>
    <li id="indicator"></li>

<button id="reset" type="button">reset</button>


                $blue: #1b3d4e;
$copper: #c07053;
$snow: #f3efeb;
$stone: #cbc0ba;

body {
  box-sizing: border-box;
  background-color: $snow;
  font-family: "Unica One", cursive;
  font-size: 16px;

nav {
  max-width: 960px;
  padding: 2.666em 1em 1.333em 1em;
  position: relative;
  background-color: $blue;
  ul {
    list-style: none;
    margin: 0;
    padding-top: 1em;
    position: relative;
    display: flex;
    justify-content: flex-start;
    li {
      // padding: 0 1.5em;
      // border: 1px solid orange;
      a {
        font-size: 1.25em;
        line-height: 1;
        letter-spacing: 0.05em;
        transition: position 1s ease;
        text-decoration: none;
        text-transform: uppercase;
        // background-color: red;
        // display: inline-block;
        margin: 0 1em 0 0;
        color: $stone;
        &.active {
          color: $copper;
    li.last {
      margin-right: 0;
  } // ul
} // nav

#indicator {
  display: block;
  width: 100px;
  height: 3px;
  background-color: lighten($copper, 10%);
  position: absolute;
  bottom: -3px;
  left: -100px;
  margin: 0;
  padding: 0;
  transition: left 700ms ease, width 700ms ease, opacity 500ms ease;
  opacity: 0;
  &.active {
    opacity: 1;
} // #indicator

#reset {
  position: fixed;
  bottom: 1em;
  right: 1em;
  background: none;
  border: none;
  font-family: inherit;
  text-transform: uppercase;
  background-color: $stone;
  padding: 0.5em 1em;
  display: none;
  &.show {
    display: block;



                // NOTES:
// Not really terribly flexible yet, as it requires a lot of hardcoding of values and it tricky to get working with right-aligned navs

// forEach method, could be shipped as part of an Object Literal/Module
function forEach(array, callback, scope) {
  for (var i = 0; i < array.length; i++) {, i, array[i]); // passes back stuff we need

// Cacheing DOM items
var indicator = document.getElementById("indicator"),
  nav = document.getElementById("main-nav"),
  navItems = document.querySelectorAll("nav > ul li a"),
  paddingCompensation = "1em",
  resetButton = document.getElementById("reset");

resetButton.addEventListener("click", function(event) {

// State
var activeState = false,

// Default position of indicator, captured from styles
var defaultSettings = {
  left: window.getComputedStyle(indicator, null).getPropertyValue("left"),
  width: window.getComputedStyle(indicator, null).getPropertyValue("width")

// If a link is "active" set the indicator's position to it instead of the default
function activeLinkSet() {
  let thisPosition = activeLink.getBoundingClientRect();
  let thisWidth = activeLink.offsetWidth;
  let thisHeight = activeLink.offsetHeight; = "calc(" + thisPosition.x + "px - 1em)"; = thisWidth + "px";

// Returns to default on hover out
function returnToDefault() { = defaultSettings.left; = defaultSettings.width;

// Logic for everything, should probably rename this since it's used on more than hover. Takes event, and a string for logic as parameters
function handleHover(e, direction) {
  if (direction === "set active") {
    // if we're setting active, run that function
  } else {
    // otherwise, check hover in or out
    if (direction === "in") {
      // if hover in, get the event target's settings and apply them.
      let thisPosition = e.currentTarget.getBoundingClientRect();
      let thisWidth = e.currentTarget.offsetWidth;
      let thisHeight = e.currentTarget.offsetHeight;
      // calc is here for difficulties with getBoundingClientRect and padding issues =
        "calc(" + thisPosition.x + "px - " + paddingCompensation + ")"; = thisWidth + "px";
    } else if (direction === "out") {
      // if hover out, set back to a default, depending on state of activeState
      if (activeState === true) {
      } else {

// for each lopps to add event listeners to links
forEach(navItems, function(index, value) {
  navItems[index].addEventListener("mouseenter", function(event) {
    handleHover(event, "in");
  navItems[index].addEventListener("click", function(event) {

// hover out is actually on the nav element itself, not the links!!!
nav.addEventListener("mouseleave", function(event) {
  handleHover(event, "out");

// fake link clicking
// could be replaced by something simpler on a real multi-page site
function handleClick(e) {
  // add active to current target
  // set state
  activeState = true;
  // set active link
  activeLink = e.currentTarget;
  // run logic function to set placement of indicator
  handleHover(e, "set active");
  // turn reset button on

function resetState() {
  activeState = false;
  // get all links
  let allLinks = document.querySelectorAll("nav a");
  // link is clicked, remove all active classes, just in case
  for (var i = 0; i < allLinks.length; i++) {