I use ipython notebook to keep my diary using the markdown cell. The problem is that The linewidth of the cell is a little too wide, not very fine looking as a blog. The question is: how can I decrease the width of the line and keep it stay in the middle(or left) of the page?
The method should be easy and not affect other cells.
You can change the CSS applied to the text cells via your custom.css
Simply add the following lines
with this the notebook looks like
There are a bunch of questions here, dealing with styling the notebook via the custom css, see e.g. here, here, or here.