template.php

<?php
function voltron_preprocess_html(&$variables) {
  //drupal_add_css('http://netdna.bootstrapcdn.com/twitter-bootstrap/2.1.1/css/bootstrap.no-icons.min.css', array('type' => 'external'));
  drupal_add_css('//netdna.bootstrapcdn.com/bootswatch/2.1.0/spacelab/bootstrap.no-icons.min.css', array('type' => 'external'));
  drupal_add_css('//netdna.bootstrapcdn.com/font-awesome/3.0.2/css/font-awesome.css', array('type' => 'external'));
  drupal_add_js('//netdna.bootstrapcdn.com/twitter-bootstrap/2.1.1/js/bootstrap.min.js','external');
}

/**
 * Custom theme function for the login/register link.
 */
function voltron_lt_login_link($variables) {
  // Only display register text if registration is allowed.
  if (variable_get('user_register', USER_REGISTER_VISITORS_ADMINISTRATIVE_APPROVAL)) {
    return t('Sign In');
  }
  else {
    return t('Log in');
  }
}

/**
 * Implementation of preprocess_page().
 */
function voltron_preprocess_page(&$vars) {
  $attr = array();

  // Replace screen/all stylesheets with print
  // We want a minimal print representation here for full control.
  if (isset($_GET['print'])) {
    $css = drupal_add_css();
    unset($css['all']);
    unset($css['screen']);
    $css['all'] = $css['print'];
    $vars['styles'] = drupal_get_css($css);

    // Add print header
    $vars['print_header'] = theme('print_header');

    // Replace all body classes
    $attr['class'] = 'print';

    // Use print template
    $vars['template_file'] = 'templates/print-page';

    // Suppress devel output
    $GLOBALS['devel_shutdown'] = FALSE;
  }
}