Make field appear using CSS and Jquery

I just want to create a field which will appear if the user clicks on a button. I know that would also work with just a simple target in CSS, but in my use, I need to do this in the way I tried it. I know it's very much CSS, but I think it shouldn't be too hard to check.

Here is my try:

function brief() {
  $('.envelope-wrapper').toggleClass('animate');
}

.envelope-wrapper {
  opacity: 0;
  width: 735px;
  height: 440px;
  left: 50%;
  margin-left: -367px;
  top: 300px;
  margin-top: -220px;
  border-radius: 10px;
  box-shadow: 0 0 3px rgba(0, 0, 0, .3);
  overflow: visible;
  background: #008da9;
}
.envelope-wrapper.animate {
  -webkit-animation-name: visible;
  -webkit-animation-duration: 2s;
  -webkit-animation-direction: forward;
  -webkit-animation-timing-function: ease-out;
}
@-webkit-keyframes visible {
  0% {
    opacity: 0;
  }
  10% {
    opacity: 10;
  }
  90% {
    opacity: 10;
  }
  100% {
    opacity: 0;
  }
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div onclick="brief()" class="gogogo">go</div>
<div class="envelope-wrapper"></div>