Check out example codes for "css class selector". It will help you in understanding the concepts better.

Code Example 1

.class{
    color:red;
}

Code Example 2

.ThisIsAClassName{
  font-family: sans-serif;
}

Code Example 3

.myclass {
  border:1px solid black;
  background-color: #d2d2d2;
  height:20px;
  width:60px;
}
/*If you give this class to a div in html, it will get the styles you gave
to that class. You can add multiple classes to a div, and multiple divs
can get that class. */
/* I hope I helped! */

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