* {
  /* border: 1px solid red; */
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: Arial, Helvetica, sans-serif;
}

a {
  text-decoration: none;
}

.container {
  max-width: 1000px;
  margin: auto;
  padding: 0 20px;
}

nav {
  height: 50px;
  border: 3px solid #000;
}

nav .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
}

.logo {
  font-weight: bolder;
  color: #000;
}

.nav-ul {
  list-style-type: none;
  display: flex;
  padding: 0;
  gap: 10px;
}

.book-list li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px;
  font-weight: bolder;
}

.nav-ul li:nth-child(2) {
  border-right: 3px solid #000;
  border-left: 3px solid #000;
  padding: 0 10px;
}

.nav-ul a {
  color: #000;
  font-weight: 500;
}

.nav-ul a:hover {
  color: #09ba09;
  transition: 0.3s ease-in;
}

header p {
  text-align: right;
  margin-top: 10px;
}

.container h1,
.container h2 {
  text-align: center;
  margin: 15px 0;
}

#time {
  margin-bottom: 10px;
}

.error {
  width: 100%;
  background: #f84242;
  margin-bottom: 10px;
  padding: 5px 0;
  text-align: center;
  color: #fff;
  font-size: 18px;
  font-weight: bolder;
}

.success {
  width: 100%;
  background: rgb(9, 186, 9);
  margin-bottom: 10px;
  padding: 5px 0;
  text-align: center;
  color: #fff;
  font-size: 18px;
  font-weight: bolder;
}

.book-list {
  list-style-type: none;
  margin: 0;
  padding: 0;
  border: 3px solid #000;
}

.book-list li:nth-child(odd) {
  background: #ccc;
}

button {
  display: inline-block;
  background: #f84242;
  color: #fff;
  font-weight: bolder;
  box-shadow: 2px 2px #000;
  padding: 0 20px;
  height: 40px;
  border: 3px solid #000;
  cursor: pointer;
}

button:hover {
  box-shadow: 5px 5px #000;
  transition: 1s ease-in-out;
}

.form-field {
  display: none;
}

.form {
  max-width: 500px;
  margin: 50px auto;
}

#title,
#author {
  display: block;
  border: 3px solid #000;
  margin: 10px 0;
  height: 30px;
  width: 100%;
  padding: 5px;
}

#title::placeholder,
#author::placeholder {
  color: #000;
  font-weight: bolder;
}

.form button {
  float: right;
  background: #09ba09;
}

.contact {
  display: none;
  width: 500px;
  margin: auto;
  padding: 30px 0;
}

.contact h3 {
  text-align: center;
  font-weight: bolder;
  font-size: 18px;
}

.contact p {
  margin-top: 50px;
  font-weight: bolder;
}

.contact ul {
  margin-top: 20px;
  font-weight: bolder;
  margin-left: 30px;
}

footer {
  border: 3px solid #000;
  height: 50px;
  position: absolute;
  width: 100%;
  bottom: 0;
}

footer .container {
  display: flex;
  justify-content: start;
  align-items: center;
  height: 100%;
}