How to assign separate CSS file for pages in ASP.NET

Question

Hai,

 

I am working in asp.net project having master page.

 

I need your help...

 

I having difficulty to assign separate css style for specific pages in my project. I wrote css style as field category. as below:-

label {
color: #555;
display: inline-block;
margin-left: 18px;
padding-top: 10px;
font-size: 14px;
}

This effected the whole project wherever I wrote lable. I want to segregate this issue.