.c-button._shiny {
    display: block;
    position: relative;
    padding: 1em 1.5em;
    background-color: #0C0C34;
    box-shadow: 0 3px 0 0 #0C0C34;
    border-radius: 10px;
  margin:30px auto;
    font-weight: bold;
    font-size: 16px;
  max-width:250px;
    color: #fff;
    text-align: center;
    text-decoration: none;
    overflow: hidden;
  transition: 300ms;
}
.c-button._shiny::before {
    position: absolute;
    content: '';
    display: inline-block;
    top: -180px;
    left: 0;
    width: 30px;
    height: 100%;
    background-color: #b5e7ff;
    transition: 300ms;
    animation: shinyshiny 2.5s ease-in-out infinite;
}

.c-button._shiny:hover {
    text-decoration: none;
    color: #fff;
    box-shadow: none;
    -webkit-transform: translateY(3px);
}

@-webkit-keyframes shinyshiny {
    0% { -webkit-transform: scale(0) rotate(45deg); opacity: 0; }
    80% { -webkit-transform: scale(0) rotate(45deg); opacity: 0.5; }
    81% { -webkit-transform: scale(4) rotate(45deg); opacity: 1; }
    100% { -webkit-transform: scale(50) rotate(45deg); opacity: 0; }
}