// *** TO BE CUSTOMISED ***

var style_cookie_name = "style" ;
var style_cookie_duration = 30 ;
var style_domain = "berkeley.edu" ;

// *** END OF CUSTOMISABLE SECTION ***
// You do not need to customise anything below this line

function switch_style ( css_title )
{
// You may use this script on your site free of charge provided
// you do not remove this notice or the URL below. Script from
// https://www.thesitewizard.com/javascripts/change-style-sheets.shtml
  var i, link_tag ;
  for (i = 0, link_tag = document.getElementsByTagName("link") ;
    i < link_tag.length ; i++ ) {
    if ((link_tag[i].rel.indexOf( "stylesheet" ) != -1) &&
      link_tag[i].title) {
      link_tag[i].disabled = true ;
      if (link_tag[i].title == css_title) {
        link_tag[i].disabled = false ;
      }
    }
    set_cookie( style_cookie_name, css_title,
      style_cookie_duration, style_domain );
  }
}
function set_style_from_cookie()
{
  var css_title = get_cookie( style_cookie_name );
  if (css_title.length) {
    switch_style( css_title );
  }
}
function set_cookie ( cookie_name, cookie_value,
    lifespan_in_days, valid_domain )
{
    // https://www.thesitewizard.com/javascripts/cookies.shtml
    var domain_string = valid_domain ?
                       ("; domain=" + valid_domain) : '' ;
    document.cookie = cookie_name +
                       "=" + encodeURIComponent( cookie_value ) +
                       "; max-age=" + 60 * 60 *
                       24 * lifespan_in_days +
                       "; path=/" + domain_string ;
}
function get_cookie ( cookie_name )
{
    // https://www.thesitewizard.com/javascripts/cookies.shtml
  var cookie_string = document.cookie ;
  if (cookie_string.length != 0) {
    var cookie_array = cookie_string.split( '; ' );
    for (i = 0 ; i < cookie_array.length ; i++) {
      cookie_value = cookie_array[i].match ( cookie_name + '=(.*)' );
      if (cookie_value != null) {
        return decodeURIComponent ( cookie_value[1] ) ;
      }
    }
  }
  return '' ;
}

function get_suffix ( cookie_name )
{
  if (get_cookie(cookie_name) == "dark") {
    return '';
  } else {
    return 'inverted';
  }
}