Improve blogpost readability

IMO readability could be improved a bit. E.g. making sure font "weightness" and contrast is proportional to semantic significance (h1 > h2 > h3 > strong?).
Also `code` should maybe be highlighted stronger?

Current rendering:
![screen shot 2013-12-22 at 21 31 33](https://f.cloud.github.com/assets/360800/1798379/4de4f210-6b48-11e3-8a60-4fa0613aaae3.png)

Go more into this direction?
![screen shot 2013-12-22 at 21 33 29](https://f.cloud.github.com/assets/360800/1798380/61c2d626-6b48-11e3-9046-dac3a7bf668d.png)

- - -

Maybe also reduce font/color variety?
Current rendering:
![screen shot 2013-12-22 at 21 34 16](https://f.cloud.github.com/assets/360800/1798384/92725aee-6b48-11e3-81b3-4aaaefb3e4c0.png)

Example http://videlalvaro.github.io/archive.html :
![screen shot 2013-12-22 at 21 36 19](https://f.cloud.github.com/assets/360800/1798387/be48acea-6b48-11e3-8549-611b06ef87e1.png)

Example http://37signals.com/svn :
![screen shot 2013-12-22 at 21 36 52](https://f.cloud.github.com/assets/360800/1798389/d1940c40-6b48-11e3-9208-70d8aab0a3d4.png)