i can add my custom css and over-ride theme's defaut css etc, Can i go this way and not use LESS.
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<head>
<link src="//fonts.googleapis.com/css?family=Raleway:400,500,500italic,600,600italic|Indie+Flower|Dosis" src_type="url" />
<css src="css/bootstrap.min.css" />
<css src="css/custom.css" />
<css src="css/styles-m.css" />
<css src="css/styles-l.css" media="screen and (min-width: 768px)"/>
<css src="css/print.css" media="print" />
</head>
</page>