Update ionic css to newest version

I have been developing ionic for a while and my project now needs slide box features. So I read that ionic 1.2 has a new slide box. I ran the commands to update my project:

npm install -g ionic
ionic lib update

It said it was update to version 1.2.4

Inside of my template I have the following code (removed < and > because it was formatting this post weird):

ion-content class="padding"
ion-slides slider="data.slider"
ion-slide-page>
div class=“box blue”>h1BLUE/h1/div
/ion-slide-page
on-slide-page
div class="box yellow"h1YELLOW/h1/div
/ion-slide-page
/ion-slides
/ion-content

This code doesn’t show up properly though. If I go to http://code.ionicframework.com/# and manually download the newest css/ionic.css file and paste it inside of my project (overwrite css/ionic.app.css) it then shows up properly. Shouldn’t the update I did have overwritten my current css file? Do I have to manually go to this page everytime to update my css and javascript files? What does ionic lib update do then?