<div class="center">
<button class="fancy">
  <span class="top-key"></span>
  <a href="#" target="_blank" class="">Buy Tickets</a>
  <span class="bottom-key-1"></span>
  <span class="bottom-key-2"></span>
</button>
</div>
<footer class="copy">  
  <p>
    <a href="https://waterproof-web-wizard.com/" title="Online Marketing Agentur">Waterproof Web Wizzard</a>      
    </p> 
</footer>

.center{
    display: flex;
  align-items: center;
  justify-content: center;
  margin-top:50px;
}


button.fancy {
  -webkit-appearance: button;
  background-color: transparent;
  border: 2px solid #000;
  border-radius: 0;
  box-sizing: border-box;
  color: #fff;
  cursor: pointer;
  display: inline-block;
  float: right;
  font-weight: 700;
  letter-spacing: .05em;
  margin: 0;
  outline: none;
  overflow: visible;
  padding: 1.25em 2em;
  position: relative;
  text-align: center;
  text-decoration: none;
  text-transform: none;
  transition: all .3s ease-in-out;
  user-select: none;
  width: 16.8125rem;
  
&::before {
    content: " ";
    width: 1.5625rem;
    height: 2px;
    background: black;
    top: 50%;
    left: 1.5em;
    position: absolute;
    -webkit-transform: translateY(-50%);
    transform: translateY(-50%);
    -webkit-transform-origin: center;
    transform-origin: center;
    -webkit-transition: background 0.3s linear, width 0.3s linear;
    transition: background 0.3s linear, width 0.3s linear;
}
  a {
    font-size: 1.125em;
    line-height: 1.33333em;
    padding-left: 2em;
    display: block;
    text-align: left;
    -webkit-transition: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
    text-transform: uppercase;
    text-decoration: none;
    color: black;
}
   
.top-key {
    height: 2px;
    width: 1.5625rem;
    top: -2px;
    left: 0.625rem;
    position: absolute;
    background: white;
    -webkit-transition: width 0.5s ease-out, left 0.3s ease-out;
    transition: width 0.5s ease-out, left 0.3s ease-out;
}
  
  .bottom-key-1 {
    height: 2px;
    width: 1.5625rem;
    right: 1.875rem;
    bottom: -2px;
    position: absolute;
    background: white;
    -webkit-transition: width 0.5s ease-out, right 0.3s ease-out;
    transition: width 0.5s ease-out, right 0.3s ease-out;
}
  .bottom-key-2 {
    height: 2px;
    width: 0.625rem;
    right: 0.625rem;
    bottom: -2px;
    position: absolute;
    background: white;
    -webkit-transition: width 0.5s ease-out, right 0.3s ease-out;
    transition: width 0.5s ease-out, right 0.3s ease-out;
}
  
    &:hover {
    color: white;
    background: black;
    
    &::before {
    width: 0.9375rem;
    background: white;
    }
    
    a {
    color: white;
    padding-left: 1.5em;
   }
    
    .top-key {
    left: -2px;
    width: 0px;
}
    .bottom-key-1 ,
    .bottom-key-2 {
    right: 0;
    width: 0;
  }
   
}

}



footer{
  background: #24df73;
  position: absolute;
  bottom: 0;
  width: 100%;
  p{
    padding: 10px;
    margin-bottom:0;
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: center;
    align-content: stretch;
    align-items: center;
    a{
      color: #000;
    }
  }
}