Upload button

You can click the button to choose a file.
<div class="container">
<!-- The real file input -->
<input type="file" class="container__input" />
<!-- The upload icon -->
<div class="container__icon">...</div>
<!-- The label -->
...
</div>
.container {
/* Used to position the input */
position: relative;
/* Center the content */
align-items: center;
display: flex;
/* Border */
border: 1px solid rgba(0, 0, 0, 0.3);
}
.container__input {
/* Take the full size */
height: 100%;
left: 0;
position: absolute;
top: 0;
width: 100%;
/* Make it transparent */
opacity: 0;
}
.container__icon {
margin-right: 8px;
}