<div id="app-cover">
  <h1 id="heading">Sign Up</h1>
  <form method="post" action="" autocomplete="off">
    <div id="inp-box-cover">
      <div id="inp-padd">
        <div class="inp-box" id="email">
          <input type="email" class="inp" placeholder="Your email address" spellcheck="false" autocomplete="off">
        </div>
        <div class="inp-box" id="username">
          <input type="text" class="inp" placeholder="Your username" spellcheck="false">
        </div>
        <div class="inp-box" id="password">
          <input type="password" class="inp" placeholder="Password (More than 5 characters)">
        </div>
        <div id="prev-action-btn"><i class="fas fa-chevron-circle-left"></i></div>
        <div id="next-action-btn"><i class="fas fa-chevron-circle-right"></i></div>
      </div>
      <div id="progress-bar-cover">
        <div id="progress">
          <div id="working">Working<i class="fas fa-sync-alt fa-spin"></i></div>
          <div id="acc-success">Account Created<i class="fas fa-check"></i><span id="init-login">Login now</span></div>
        </div>
      </div>
    </div>
  </form>
</div>

* {
  outline: none;
}

html,
body {
  height: 100%;
  min-height: 100%;
}

body {
  margin: 0;
}

input {
  display: block;
  width: 100%;
  color: #424245;
  font-size: 16px;
  padding: 0;
  margin: 0;
  border: 0;
  background-color: transparent;
}

input::-webkit-input-placeholder {
  color: #9999a2;
}

input:-ms-input-placeholder {
  color: #9999a2;
}

input::-moz-placeholder {
  color: #9999a2;
  opacity: 1;
}

input:-moz-placeholder {
  color: #9999a2;
  opacity: 1;
}

#password input::placeholder {
  font-weight: normal;
  letter-spacing: 0;
}

#password input {
  font-weight: bold;
  letter-spacing: 4px;
}

#password input::-webkit-input-placeholder {
  font-weight: normal;
  letter-spacing: 0;
}

#password input:-ms-input-placeholder {
  font-weight: normal;
  letter-spacing: 0;
}

#password input::-moz-placeholder {
  font-weight: normal;
  letter-spacing: 0;
}

#password input:-moz-placeholder {
  font-weight: normal;
  letter-spacing: 0;
}

body,
input {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

#app-cover {
  position: absolute;
  top: 50%;
  right: 0;
  left: 0;
  max-width: 420px;
  padding: 20px;
  margin: -70px auto 0 auto;
}

#heading {
  color: #5f5f64;
  font-size: 30px;
  font-weight: bold;
  line-height: 1;
  margin: 0 0 20px 0;
}

#inp-box-cover {
  position: relative;
  width: 111px;
  height: 6px;
  background-color: #f4f4f4;
  border-radius: 4px;
  overflow: hidden;
  transition: 0.5s cubic-bezier(0.65, 0.05, 0.36, 1) all, 0s ease border;
}

#heading {
  transition: 0.5s cubic-bezier(0.65, 0.05, 0.36, 1) all;
}

#app-cover.active #heading {
  margin-top: -57px;
  margin-bottom: 77px;
}

#app-cover.active #inp-box-cover {
  width: 420px;
  height: 57px;
  margin-top: -57px;
  border: 1px solid #5f5f64;
  box-shadow: inset 0 2px 2px #fff;
}

#inp-padd {
  padding: 15px 0 21px 15px;
}

.inp-box {
  position: relative;
  bottom: -36px;
  padding-right: 87px;
  opacity: 0;
  transition: 0.6s ease-in-out all, 1.2s ease-out opacity;
}

.inp-box.active {
  bottom: 0;
  opacity: 1;
}

.inp-box#username.active {
  bottom: 21px;
}

.inp-box#password.active {
  bottom: 42px;
}

.inp-box.inactive {
  bottom: 36px;
  opacity: 0;
}

.inp-box#username.inactive {
  bottom: 57px;
}

.inp-box#password.inactive {
  bottom: 78px;
}

#prev-action-btn,
#next-action-btn {
  position: absolute;
  top: 0;
  right: 15px;
  bottom: 0;
  width: 28.5px;
  height: 51px;
  cursor: pointer;
  overflow: hidden;
}

#prev-action-btn {
  right: 43.5px;
}

#next-action-btn i,
#prev-action-btn i {
  position: relative;
  left: -5px;
  display: block;
  width: 21px;
  color: #5f5f64;
  font-size: 21px;
  padding: 15px 0 15px 7.5px;
  line-height: 1;
  opacity: 0;
  transition: 0.3s ease-in-out all;
  cursor: pointer;
}

#prev-action-btn i {
  left: 5px;
  padding-left: 0;
  padding-right: 7.5px;
}

#prev-action-btn.active i,
#next-action-btn.active i {
  left: 0;
  opacity: 1;
}

#progress-bar-cover {
  position: absolute;
  top: 51px;
  bottom: 0;
  left: 0;
  height: 6px;
  width: 100%;
  background-color: #e7e7e7;
  transition: 0.5s ease all;
  z-index: 1;
}

#progress-bar-cover.hide-form {
  top: 0;
  height: 100%;
}

#progress {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  color: transparent;
  width: 0%;
  background-color: #5f5f64;
  transition: 0.5s ease all;
}

#progress-bar-cover.hide-form #progress {
  width: 100%;
  color: #fff;
  text-align: center;
  padding: 16px 0;
}

#progress i {
  margin-left: 5px;
}

#working {
  font-size: 16px;
  line-height: 1;
  padding: 3.5px;
  transform: scale(1);
  display: none;
}

#working.inactive {
  transform: scale(0);
  transition: 0.5s ease all;
}

#working i {
  position: relative;
  top: -1px;
  display: inline-block;
  color: #9c9c9c;
  font-size: 15px;
  margin-left: 5px;
  vertical-align: middle;
}

#acc-success {
  position: absolute;
  top: 57px;
  right: 0;
  left: 0;
  padding: 16px 0;
  opacity: 0;
  transition: 0.5s ease all;
}

#acc-success.active {
  top: 0;
  bottom: 0;
  opacity: 1;
}

#init-login {
  float: right;
  font-size: 14px;
  line-height: 1;
  padding: 6px 10px 8px 10px;
  margin: -1px 15px 0 0;
  cursor: pointer;
  border-radius: 20px;
  background-color: #7d7d7d;
  box-shadow: 0 0 0 1px #4d4d4d;
}

$(function () {
  var app_cover = $("#app-cover"),
    inp = $(".inp"),
    prevAction = $("#prev-action-btn"),
    nextAction = $("#next-action-btn"),
    stepComplete = false,
    progress = $("#progress"),
    timeOut = null,
    stepsArr = ["email", "username", "password"],
    stepNumber = 1,
    lastCompletedStep = 0,
    totalSteps = stepsArr.length;

  function checkApp() {
    if (stepNumber > 1) return;

    var active = false;
    inp.each(function () {
      if ($(this).val().trim().length > 0) active = true;
    });

    if (active) app_cover.addClass("active");
    else {
      app_cover.removeClass("active");
      inp.parent("div").removeClass("active");
    }
  }

  function _a() {
    nextAction.addClass("active");
    stepComplete = true;
    if (lastCompletedStep < stepNumber) lastCompletedStep = stepNumber;
  }

  function _b() {
    nextAction.removeClass("active");
    stepComplete = false;
  }

  function checkInput() {
    var _this = $(this),
      regex,
      index = stepNumber - 1,
      _val = _this.val().trim();
    if (stepsArr[index] == "email") {
      regex = /^([a-zA-Z0-9_.+-])+\@(([a-zA-Z0-9-])+\.)+([a-zA-Z0-9]{2,4})+$/;
      if (regex.test(_val)) _a();
      else _b();
    } else if (stepsArr[index] == "username") {
      clearTimeout(timeOut);
      timeOut = setTimeout(function () {
        if (_val.length > 0) _a();
        else _b();
      }, 500);
    } else if (stepsArr[index] == "password") {
      if (_val.length >= 5) _a();
      else _b();
    }
  }

  function clearForm() {
    inp.val("");
    $(".inp-box").removeClass("active inactive");
    nextAction.removeClass("active");
    prevAction.removeAttr("class");
    nextAction.removeAttr("class");
  }

  function moveToPreviousStep() {
    --stepNumber;

    if (stepNumber < 1) {
      stepNumber = 1;
      prevAction.removeClass("active");
      return;
    } else {
      if (stepNumber == 1) prevAction.removeClass("active");

      if (stepNumber <= lastCompletedStep) stepComplete = true;

      nextAction.addClass("active");

      progress.width(((stepNumber - 1) / totalSteps) * 100 + "%");
      $("#" + stepsArr[stepNumber]).removeClass("active");
      $("#" + stepsArr[stepNumber - 1]).removeClass("inactive");
    }
  }

  function moveToNextStep() {
    if (
      stepComplete &&
      $("#" + stepsArr[stepNumber - 1])
        .find(".inp")
        .val()
        .trim().length > 0
    ) {
      progress.width((stepNumber / totalSteps) * 100 + "%");

      prevAction.addClass("active");

      if (stepNumber == totalSteps) {
        setTimeout(function () {
          $("#progress-bar-cover").addClass("hide-form");

          $("#working").fadeIn(0);

          setTimeout(function () {
            $("#working").addClass("inactive");
            clearForm();
          }, 2300);

          setTimeout(function () {
            $("#acc-success").addClass("active");
          }, 3300);
        }, 500);

        return;
      }

      $("#" + stepsArr[stepNumber - 1]).addClass("inactive");
      $("#" + stepsArr[stepNumber]).addClass("active");

      if (stepNumber > lastCompletedStep) {
        lastCompletedStep = stepNumber;
        stepComplete = false;
      }

      ++stepNumber; // Now on next step

      if (
        stepNumber <= lastCompletedStep &&
        $("#" + stepsArr[stepNumber - 1])
          .find(".inp")
          .val()
          .trim().length > 0
      )
        nextAction.addClass("active");
      else nextAction.removeClass("active");
    }
  }

  app_cover.hover(
    function () {
      var f_elm = $("#" + stepsArr[0]);
      if (!$(this).hasClass("active")) {
        $(this).addClass("active");
        f_elm.addClass("active");
        setTimeout(function () {
          f_elm.find("input").focus();
        }, 1205);
        stepNumber = 1;
        lastCompletedStep = 0;
        stepComplete = false;
      }
    },
    function () {
      checkApp();
    }
  );

  inp.on("keyup", checkInput);

  prevAction.on("click", moveToPreviousStep);
  nextAction.on("click", moveToNextStep);
});