My site is all plain HTML no matter which theme i use

i don’t know how this happened but my new blog http://www.UjjwalKumar.co.in/ looks just plain HTML no matter which theme i use.. i am new to wordpress and don’t know much consider me a noob. and when i log into the Dashboard it looks so yucky like plain html… other site look fine but why is this happening with me only i even asked my friends they say its nothing but just looks like plain HTML help plz!