I created a shortcode that works, but the color only shows on first paragraph

Hi all,

I thought I’d have a go at creating some shortcodes to make life a little easier. The idea of this one is to create a a nice curved area which is darker than the background with a lighter text.

For some reason, everything seems to work ok on it, I get the full curved area between the shortcode, which is [dark1] and [/dark1] but the text only changes color on the first paragraph, as you can see here:

https://sylv-jenkins.com/test-page

The code used was this:

functions.php

function dark1( $atts, $content = null ) {
	return '<div class="sc-dark1">"'.$content.'"</div>';
}

add_shortcode("dark1", "dark1");

CSS

.sc-dark1 {
background: #575970;
color: #afb0bc;
padding: 10px;
border-radius: 20px;
}

I can’t figure out what I may have done wrong, so any help is very much appreciated (especially as this is my wife’s site).

Thanks.