@media screen and (max-width: 480px) {
  #gallery li:nth-child(3n) {
    clear: left;
  }
}

@media screen and (min-width: 480px) {

  /*****************************************************
  TWO-COLUMN LAYOUT
  ******************************************************/

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

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



  /*****************************************************
  PAGE: LIST
  ******************************************************/

  #gallery li {
    width: 28.3333%;
  }

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

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

}
@media screen and (max-width: 480px) {
  #gallery li:nth-child(3n) {
    clear: left;
  }
}

@media screen and (min-width: 480px) {

  /*****************************************************
  TWO-COLUMN LAYOUT
  ******************************************************/

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

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



  /*****************************************************
  PAGE: LIST
  ******************************************************/

  #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) {

}
Make two-column layout for 'about' page
Make two-column layout for 'about' page
