Or better yet
some <span class="alert">alerted</span> text
with a class
.alert {color:#ff0000}
in the stylesheet.
Otherwise you're kinda missing the point of CSS, which is to separate the HTML content from the styling it happens to be rendered in - and you might as well go back to using <font> tags. 🙂
After all, you might decide "no, I don't want alerts to be red, I want them BIGGER". With the stylesheet you have precisely one point that needs changing; with <span style="color:red"> you'll have to go through all the HTML that might contain the style and replace it - not forgetting to change <span style="color:#ff0000">, <span style="color:#f00">, <span="color:rgb(255,0,0)"> and so on, and not forgetting that you might not want to change some because they're red for some other reason.....