I'm trying to move the label to above the input field when I focus, but it gets hidden instead

Question

I'm trying to move the label to above the input field when I focus, but it gets hidden instead.

label > span::focus  {
  top: -20px; 
  font-size: 15px;
  color: blue;           
} 

Complete Html & CSS code.

Update:

I figured it out, I just change some HTML classes and things to this:

.user-input:focus + .user-label > span { 
  margin-top: -15px;
  font-size: 10px;
  color: blue;      

Answer 1

As I said in comment: You can not style previous sibling selector(label) on focus the next(input)

So you have to set the label after input in html and set position:relative instead of absolute

See code:

body {
  background-color: #f0f0f0;
}

form {
  margin-left: 39%;
  margin-top: 9%;
}
label {
  position: relative;
  margin-left: 0%; 
  font-family: monospace, 'Montserrat', sans-serif;
  font-size: 15px;
  padding-top: 3px; 
 /* border: 5px solid black;*/ 
}

.head {
margin-left: 43%;
margin-top: 5%;
font-size: 25px;
font-family: monospace;

}

.password {
  margin-top: 5%; 
}


.input-field {
  position: absolute;
  background: transparent;
  border-width: 2px;
  border-top: 0;
  border-left: 0;
  border-right: 0;
  background: transparent;
  outline: 0;
  height: 23px;
  border-color: black;
  width: 180px;
} 


input:focus {
  background: #fae596;
  border: 0;
}

input:focus + .label   {
  top:-20px; 
  font-size: 15px;
  color: blue;           /* font color while on top */
}

 <p class="head">Sign In</p>
<form>

    <div class="username">	
      
      <input type="text" name="name" class="input-field" id="user"/> <!--input filed-->
      <label for="user" class="label"><span>Username</span></label>
    </div>

    <br>
    <br>
    <div class="password">
      <input type="text" name="name" class="input-field" id="pass" />
      <label for="pass" class="label"><span>Password</span></label>
    </div>
  
  
</form>

Answer 2

I think You Need Something Like This

  

 * {
	box-sizing: border-box;
}

.group {
	position: relative;
	margin-bottom: 45px;
	margin-top: 45px;
}

input {
	font-size: 18px;
	padding: 10px 10px 10px 5px;
	display: block;
	width: 300px;
	border: none;
	border-bottom: 1px solid #757575;
}

input:focus {
	outline: none;
}

label {
	color: #999;
	font-size: 18px;
	font-weight: normal;
	position: absolute;
	pointer-events: none;
	left: 5px;
	top: 10px;
	transition: 0.2s ease all;
	-moz-transition: 0.2s ease all;
	-webkit-transition: 0.2s ease all;
}

input:focus~label,
input:valid~label {
	top: -20px;
	font-size: 14px;
	color: #5264AE;
}

input:focus~.bar:before,
input:focus~.bar:after {
	width: 50%;
}

.highlight {
	position: absolute;
	height: 60%;
	width: 100px;
	top: 25%;
	left: 0;
	pointer-events: none;
	opacity: 0.5;
}


/* active state */

input:focus~.highlight {
	-webkit-animation: inputHighlighter 0.3s ease;
	-moz-animation: inputHighlighter 0.3s ease;
	animation: inputHighlighter 0.3s ease;
}


/* ANIMATIONS ================ */

@-webkit-keyframes inputHighlighter {
	from {
		background: #5264AE;
	}
	to {
		width: 0;
		background: transparent;
	}
}

@-moz-keyframes inputHighlighter {
	from {
		background: #5264AE;
	}
	to {
		width: 0;
		background: transparent;
	}
}

@keyframes inputHighlighter {
	from {
		background: #5264AE;
	}
	to {
		width: 0;
		background: transparent;
	}
}

<form>
    
    <div class="group">      
      <input type="text" required>
      <span class="highlight"></span>
      <span class="bar"></span>
      <label>Name</label>
    </div>
      
    <div class="group">      
      <input type="text" required>
      <span class="highlight"></span>
      <span class="bar"></span>
      <label>Email</label>
    </div>
    
  </form>