How to use custom css for phone and tab in ios in sass?

I have understood little about sass. In style.css i have written like
.item-input-inset .item-input-wrapper input {
background: none repeat scroll 0 0 transparent;
height: 29px;
line-height: 18px;
padding-left: 2px;
i don’t know how to use it within my project through sass for phone and
tab. This css works nice for phone. i have written a lot of css in
style.css . Above is only sample.

Note: I have set up sass in my project. In i have used

$positive: teal !default;
It is working fine.
Please help me and write about steps to follow.

SASS is a superset of CSS. Anything you write in CSS will work in SASS so you should be able to take anything you have in styles.css, paste it in ionic.apps.sass and it should work.