style.css

body {
  font-family: 'Comic Neue', cursive;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin: 0;
  font-size: 2rem;
}

.main-box {
  flex: 1;
  max-width: 600px;
  margin: 0 auto;
  padding: 20px;
  box-sizing: border-box;
}

.user-box {
  position: relative;
  margin-bottom: 20px;
}

.user-box input {
  width: 100%;
  padding: 8px;
  font-size: 16px;
  border: none;
  border-bottom: 1px solid #aaa;
  outline: none;
  background-color: transparent;
}

.user-box label {
  position: absolute;
  top: 0;
  left: 0;
  padding: 8px;
  font-size: 16px;
  color: #555;
  pointer-events: none;
  transition: 0.2s ease-out;
}

.user-box input:focus ~ label,
.user-box input:valid ~ label {
  top: -20px;
  left: 0;
  color: #777;
  font-size: 14px;
}

h2 {
  text-align: center;
  margin-top: 20px;
}

#books {
  margin-top: 20px;
  text-align: center;
}

#books .user-box {
  margin-bottom: 10px;
}

#bookContainer {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.book {
  width: 100%;
  padding: 10px;
  border: 1px solid #ccc;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 45px;
}

.book-title {
  flex: 1;
  font-weight: bold;
}

.book-author {
  color: #555;
}

.remove-button {
  background-color: #ff6347;
  color: #fff;
  border: none;
  padding: 5px 10px;
  text-decoration: none;
  cursor: pointer;
}

.remove-button:hover {
  background-color: #cc4338;
}

.add-button {
  display: inline-block;
  padding: 10px 20px;
  margin-top: 20px;
  background-color: #4caf50;
  color: #fff;
  border: none;
  cursor: pointer;
}