I am not sure why my header page and about page is not being responsive when i am doing my responsive.css.

@media screen and (min-width: 480px) { /**************************** two column layout ****************************/

#primary { width: 50%; float: left; }

#secondary { width: 40%; float: right;
}

/**************************** page: portfolio ****************************/

#gallery li { width: 28.3333%; }

#gallery li:nth-child(4n) { clear: left; }

/**************************** page: About

****************************/

.profile-photo { float: left; margin: 0 5% 80px 0;
}

@media screen and (min-width:660px) {

/**************************** header ****************************/

nav {
  background: none;
  float: right;
  font-size: 1.125em;
  margin-right: 5%;
  text-align: right;
  width: 45%;
}

}