.logo {
  display: block;
  margin-left: auto;
  margin-right: auto;
  width: 150px;
  height: 150px;
  
}
.btn-login{
  width: 100%;
  background: -moz-linear-gradient(top, #b530c7, #feb47b); /* Firefox */
  background: -webkit-linear-gradient(top, #431796, #35f51b); /* Chrome, Safari */
  background: linear-gradient(to bottom, #152013, #b530c7); /* Standard syntax */
  color: white;
}
.form-control {
  width: 100%;
}
  /* Normal desktop :1200px. */
@media (min-width: 1200px) and (max-width: 1500px) {

  .btn-login{
    width: 80%;
  }
}


/* Normal desktop :992px. */
@media (min-width: 992px) and (max-width: 1200px) {
  .btn-login{
    width: 80%;
  }

}

 
/* Tablet desktop :768px. */
@media (min-width: 768px) and (max-width: 991px) {


}

 
/* small mobile :320px. */
@media (max-width: 767px) {

 
}
 
/* Large Mobile :480px. */
@media only screen and (min-width: 480px) and (max-width: 767px) {
.container {width:450px}
 
}