Bootstrap 3 Template

Only allowing a user to proceed if they upload a file

HTML

<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<div class="container">
<div class="row">
    <input class="file-input" type="file" accept="image/*" name="fileUpload" id="fileUpload" capture="camera">
    <label for="fileUpload" id="file-upload-btn">Capture or Upload Photo</label>
</div>
<div class="row padding-top-two-em">
    <input class="btn btn-success hidden" id="accept-btn" type="submit" value="Accept & Continue"/>
    <button class="btn btn-danger">Back</button>
</div></div>

CSS

.file-input {
	width: 0.1px;
	height: 0.1px;
	opacity: 0;
	overflow: hidden;
	position: absolute;
	z-index: -1; 
}

.file-input + label {
    font-size: 1.25em;
    font-weight: normal;
    color: white;
    background-color: blue;
    display: inline-block;
    padding: 5px;
}

.file-input:focus + label,
.file-input + label:hover {
    background-color: red;
}

.file-input + label {
	cursor: pointer;
}

.file-input + label * {
	pointer-events: none;
}

JavaScript

$('#fileUpload').change(function () {
        var fileName = $('#fileUpload').val();
        if (fileName != "") {
            $('#file-upload-btn').html(fileName);
            $('#accept-btn').removeClass('hidden').addClass('show');
        } else {
            $('#file-upload-btn').html("Upload File");
            $('#accept-btn').addClass('hidden');
        }
    });