Edit in JSFiddle

.button {
    background-color: #CCCCFF;
    border: none;
    height: 55px;
    width: 155px;
    color: #000;
    text-decoration: none;
    text-align: center;
    line-height: 55px;
    font-size: 14px;
    letter-spacing: 1px;
    font-weight: 300;
    font-family: Roboto,sans-serif;
    animation: neweffects 3s infinite
 }

.button:hover {
    background-color: #99FFCC;
    cursor: pointer;
 }
  
  @keyframes neweffects {
  0% {
      transform: scale(1);
   }
  50% {
      transform: scale(1.05);
      background-color: #99FFCC;
   }
  100% {
      transform: scale(1);
   }
}   
<div class="button">
<input value="Войти" class="button">
</div>