Hello,

The provided code supposed the checkbox is located after the form. Please replace the code with this one:

.mc4wp-form p:first-child label {
	display: block;
}

body .mc4wp-form>div>p {
		max-width: 100%;
		flex-basis: 100%;
		width: 100%;
}

You will get this result: http://prntscr.com/mjglzf

Best Regards