input[type="text"] {
  display: block;
  margin: auto;
  width: 250px;
  font-family: sans-serif;
  font-size: 18px;
  appearance: none;
  box-shadow: none;
  border-radius: none;
}
input[type="text"]:focus {
  outline: none;
}

.search-box{
  display: block;
    height: 100px;
    width: 400px;
    margin: 50px auto auto;
}

.search-box input[type="text"] {
  padding: 10px;
  border: none;
  border-bottom: solid 2px #c9c9c9;
  transition: border 0.3s;
  outline: 30px solid #efefef;
}
.search-box input[type="text"]:focus,
.search-box input[type="text"].focus {
  border-bottom: solid 2px #969696;
}