I'm regularly editing CSS in Vim and need to change a value like:

```
width: 300px;

```

to something else like:

```
width: 178px;

```

Normally what I do is navigate to the 3 in 300 and type `cw` to change the word. But if I do this I have to type the `px` bit again. Is there a short and quick way to say `change in digits`.

In my searching I've discovered Ctrl-a and Ctrl-x to increment and decrement numbers in this situation. Is there an equivalent for being able to retype the number?

I should clarify that the ideal solution would require the fewest keystrokes at time of operation and support modifications to different length numbers. Like if I wanted to change 300px to 17px.