WooCommerce: Change Quantity on Shop Page

/**
 * Add quantity fields to Shop/Category pages.
 */
function webroom_add_quantity_fields($html, $product) {
	
	//add quantity field only to simple products
	if ( $product && $product->is_type( 'simple' ) && $product->is_purchasable() && $product->is_in_stock() && ! $product->is_sold_individually() ) {
		
		//rewrite form code for add to cart button
		$html = '<form action="' . esc_url( $product->add_to_cart_url() ) . '" class="cart" method="post" enctype="multipart/form-data">';
		$html .= woocommerce_quantity_input( array(), $product, false );
		$html .= '<button type="submit" data-quantity="1" data-product_id="' . $product->get_id() . '" class="button alt ajax_add_to_cart add_to_cart_button product_type_simple">' . esc_html( $product->add_to_cart_text() ) . '</button>';
		$html .= '</form>';
	}
	return $html;
}

/**
 * Add AJAX support
 * Sync quantity field
 */
function webroom_quantity_handler() {

	wc_enqueue_js( '
	jQuery(function($) {
	$("form.cart").on("change", "input.qty", function() {
	$(this.form).find("[data-quantity]").attr("data-quantity", this.value);  //used attr instead of data, for WC 4.0 compatibility
	});
	' );

	wc_enqueue_js( '
	$(document.body).on("adding_to_cart", function() {
		$("a.added_to_cart").remove();
	});
	});
	' );
	
	wc_enqueue_js( '
	$(document.body).on("added_to_cart", function( data ) {

	$(".added_to_cart").after("<p class=\'confirm_add\'>Item Added</p>");
	});
	' );
	
}

add_action( 'init', 'webroom_quantity_handler' );
add_filter( 'woocommerce_loop_add_to_cart_link', 'webroom_add_quantity_fields', 10, 2 );

html[lang="en-US"] .quantity:before {/* add another entry for translation */
	content:"Quantity:"; /* text before input */
	margin-right:10px
}

.quantity {
	margin: 0 auto;
    margin-bottom: 15px;
}