cssで文字をクリックしたら赤いばつ印が入るアニメーションを作りたい。

.b__text {
  display: inline-block;
  position: relative;
}
a:hover .b__text {
  background-color: white;
  color: black;
}
a:active .b__text::after {
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cstyle%3Epath%7Bfill:none;stroke:red%7D%3C/style%3E%3C/defs%3E%3Cpath d='M0,0L16,16M16,0L0,16' /%3E%3C/svg%3E%0A") no-repeat center/100% 100%;
  content: '';
  display: block;
  height: 100%;
  left: 0;
  position: absolute;
  top: 0;
  width: 100%;
}

  <section class="message wow animate__animated animate__fadeIn" data-wow-offset="100">
    <div class="message-inner">
      <h2 class="message-title">
        <span class="message-main">テキスト１</span>
      </h2>
      <div class="message-text wow fadeInUp">
        <div class="blog-link cmn-link">

          <a target="_blank" class="btn_ao_b  wow fadeInUp"><span class="b__text ">　選択肢１</span></a>

          <a href="<?php echo home_url('contact'); ?>" target="_blank" class="btn_ao_b wow fadeInUp"><span class="b__text">選択肢２</span></a>
        </div>
      </div>
    </div>
  </section>

.cmn-link a.btn_ao_b {
  color: #fff;
  background-color: #000;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  height: 37px;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 14px;
}

@media print, screen and (min-width: 768px) {
  .cmn-link a.btn_ao_b {
    height: 20px;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
    max-width: 100px;
    margin: 0 20px 0 auto;
    padding: 1rem 1rem;
    border: 2px solid #000;
    background: #000;
    text-decoration: none;
    -webkit-transition: 0.3s;
    transition: 0.3s;
  }
  .cmn-link a.btn_ao_b + a.btn_ao_b {
    margin: 0 0 0 20px;
  }
}

@media print, screen and (min-width: 768px) and (min-width: 768px) {
  .cmn-link a.btn_ao_b {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    max-width: 300px;
  }
}

.cmn-link a.btn_ao_b:hover {
  -webkit-transform: scale(1.1);
  transform: scale(1.1);
}

.cmn-link a.btn_ao_b .b__text {
  display: block;
  font-size: 14px;
  padding-right: 20px;
  padding-left: 20px;
}

@media print, screen and (min-width: 768px) {
  .cmn-link a.btn_ao_b .b__text {
    display: block;
    -webkit-box-flex: 1;
    -ms-flex-positive: 1;
    flex-grow: 1;
    color: #fff;
    font-weight: normal;
    text-align: center;
    position: relative;
    padding-right: 15px;
    font-size: 20px;
  }
}

.cmn-link a.btn_ao_b .b__text::after {
  width: 10px;
  height: 10px;
}

@media print, screen and (min-width: 768px) {
  .cmn-link a.btn_ao_b .b__text::after {
    content: "";
    position: absolute;
    top: 0;
    bottom: 0;
    right: 0;
    margin: auto;
    -webkit-transform: rotate(45deg);
    transform: rotate(45deg);
    border-top: 1px solid #fff;
    border-right: 1px solid #fff;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
    width: 14px;
    height: 14px;
    -webkit-transition: 0.3s;
    transition: 0.3s;
  }