text: var path = require('path');
  var ejs = require('ejs');
  var fs = require('hexo-fs');
  
  var layout = 'layout.ejs';
  var bodyTag = '</body>';
  var mathjaxScript = fs.readFileSync(path.join(__dirname, 'mathjax.html'));
  
  hexo.extend.renderer.register('ejs', 'html', function(data, options, callback) {
      var path = options.filename = data.path;
      var content = data.text;
      if (layout === path.substring(path.length - layout.length))
          content = content.replace(bodyTag, mathjaxScript + '\n' + bodyTag);
      callback(null, ejs.render(content, options));
  });
  