modalzinha.css

/*
* Modalzinha.js
*
* by Fernando Soares (@frrrnd)
* github.com/frrrnd/modalzinha-js
*
*/

.modal-wrapper { 
  width: 100%; 
  height: 100%; 
  min-height: 100%; 
  position: fixed; 
  top: 0; 
  left: 0; 
  background-color: rgba(0,0,0,.7); 
  transition: .4s; 
  visibility: hidden; 
  opacity: 0; 
  z-index: 100;
}

.modal-content { 
  max-width: 800px;
  width: 100%;
  position: absolute;
  top: 30%;
  left: 0;
  right: 0;
  margin: 0 auto;
  z-index: 10;
  background-color: #fff;
}

.modal-opened { 
  opacity: 1; 
  visibility: visible;
}