on_hover_button.css in Better Search Block 7

i.better_search {
  background: url("images/search-icon.svg") center center no-repeat;
  height: 1.1em;
  width: 1em;
  font-style: normal;
  font-weight: normal;
  line-height: 1;
  -webkit-font-smoothing: antialiased;
  display: inline-block;
}

#search-block-form {
  overflow: hidden;
  vertical-align: middle;
  white-space: nowrap;
}

.form-item-search-block-form input.form-text {
  height: 50px;
  background: #2b303b; /* Search field BG */
  border: none;
  font-size: 1em;
  float: left;
  color: #fff;
  padding-left: 15px;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  border-radius: 5px; 
  z-index: 100;
}

#search-block-form .icon {
  border: none;
  height: 50px;
  width: 50px;
  color: #4f5b66;
  opacity: 0;
  -webkit-transition: all .55s ease;
  -moz-transition: all .55s ease;
  -ms-transition: all .55s ease;
  -o-transition: all .55s ease;
  transition: all .55s ease;
}

.form-item-search-block-form input:-webkit-input-placeholder {
  color: #65737e;
}
 
.form-item-search-block-form input:-moz-placeholder {
  color: #65737e;
}

.form-item-search-block-form input:-ms-input-placeholder {
  color: #65737e;
}

#search-block-form:hover .icon,
#search-block-form:focus .icon,
#search-block-form:active .icon {
  outline: none;
  opacity: 1;
  margin-left: -50px;
}

#search-block-form:hover {
  cursor: pointer;
  cursor: hand;
}

#search-block-form:hover .icon {
  background: white;
}