A snake-made semi-finished product written in jquery+html

Always want to use JQUERY+HTML+CSS to complete a game, from the classic greedy snake start. Directly on the code:

<! DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 transitional//en" "Http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">
You can copy and run a bit.
But I still have the following unfinished work:
1, after eating the food, the snake did not add itself to a lattice, that is, add a long body;
2, the snake in one lattice to the winding movement;
3, the greedy snake bit his body, game over;
Suffering from their own ability to limit, has not thought of a better solution, welcome Bo friends to provide ideas (language environment is set in JQ+HTML+CSS3). Thank you!
A snake-made semi-finished product written in jquery+html