:root {
  --color-filler: #f14949;
  --color-liner: #f6eeee;
}

* {
  box-sizing: border-box;
}

body {
  background-color: var(--color-filler);
  font-family: Georgia, 'Times New Roman', Times, serif;
  margin: 0;
  overflow: hidden;
  height: 100vh;
  padding: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.search {
  position: relative;
  display: flex;
  justify-content: center;
  gap: 3%;
}

.input {
  background-color: var(--color-liner);
  height: 45px;
  width: 2.5rem;
  border: 5px solid springgreen;
  border-radius: 10px;
  padding: 5px;
  transition: width 0.3s ease;
}

.btn {
  height: 45px;
  width: 2.5rem;
  border: 5px solid springgreen;
  border-radius: 30%;
  font-size: 22px;
  position: absolute;
  top: 0;
  left: 0;
  transition: transform 0.3s ease;
}

.fa-search {
  color: var(--color-filler);
}

.btn:focus,
.input:focus {
  outline: none;
}

.search.active .input {
  width: 22rem;
}

.search.active .btn {
  transform: translateX(23rem);
}