Style http://example.com/student-login/ form and page?

The log inn page and form does, mildly spoken, looks terrible. Can someone tell me the best way to begin to modify it and other elements of the course pages?(What/where CSS file?)

    Predrag Dubajic

    Hey @Åge

    Hope you're doing well today

    You shouldn't change themes and plugins CSS files, that way the changes will get overwritten with the theme update.
    You may wish to use a child theme or a plugin like this one for any additional CSS.

    Here is some CSS code for your login page to get you started:

    #student-settings p,
    #student-settings .half-left {
    	clear: both;
    }
    
    #student-settings .apply-button-enrolled {
    	float: left;
    	font-family: 'Raleway', Arial, sans-serif;
    	font-size: 12px;
    	font-weight: 400 !important;
    	color: #666;
    	background-color: #ddd;
    	width: 34%;
    	margin: 0 0 0 -4px;
    	padding: 11px 10px 10px 10px !important;
    	border: none;
    	-webkit-border-top-right-radius: 3px;
    	-webkit-border-bottom-right-radius: 3px;
    	-moz-border-radius-topright: 3px;
    	-moz-border-radius-bottomright: 3px;
    	border-top-right-radius: 3px;
    	border-bottom-right-radius: 3px;
    	width: 63px;
    	height: 31px !important;
    	line-height: 1;
    }
    
    input[type=password] {
    	background-color: #fff;
    	border: 1px solid #bbb;
    	padding: 2px;
    	color: #4e4e4e;
    	font-size: 1em;
    }

    Best regards,
    Predrag