Material Floating Label Input

<!--
  Author: @codepeek
  License: MIT
  Tags: #buttons #css #interface #opensource #codepeek
-->
<div class="mat-input-group">
  <input type="text" id="username" class="mat-input" placeholder=" " required />
  <label for="username" class="mat-label">Username</label>
  <span class="mat-line"></span>
</div>

/*
 * Author: @codepeek
 * License: MIT
 * Tags: #buttons #css #interface #opensource #codepeek
 */

.mat-input-group { position: relative; width: 200px; font-family: system-ui, sans-serif; }
.mat-input { width: 100%; padding: 10px 0 6px 0; border: none; border-bottom: 1px solid #52525b; background: transparent; font-size: 13px; color: #fff; outline: none; box-sizing: border-box; }
.mat-label { position: absolute; top: 10px; left: 0; font-size: 13px; color: #71717a; pointer-events: none; transition: 0.2s ease all; }
.mat-line { position: absolute; bottom: 0; left: 0; width: 0; height: 2px; background: #6366f1; transition: 0.2s ease all; }
.mat-input:focus ~ .mat-line, .mat-input:not(:placeholder-shown) ~ .mat-line { width: 100%; }
.mat-input:focus ~ .mat-label, .mat-input:not(:placeholder-shown) ~ .mat-label { top: -12px; font-size: 10px; color: #6366f1; font-weight: 700; }