/* =========================================
   GENERAL BODY STYLING
========================================= */
body {
  margin: 0;
  font-family: "Roboto", sans-serif;
  background: linear-gradient(rgba(31, 154, 255, 0.6), rgba(42, 149, 255, 0.6)),
    url("img/bg.jpg") no-repeat center center/cover;
  background-attachment: fixed;
  color: #333;
}

/* =========================================
   NAVBAR
========================================= */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  background-image: linear-gradient(270deg, #0f2027 0%, #1c5092 100%);
  padding: 10px 20px;
  color: white;
  position: relative;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: bold;
  font-size: 18px;
}

.logo-img {
  height: 60px;
  object-fit: contain;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
}

.nav-links li a {
  color: white;
  text-decoration: none;
  font-size: 14px;
}

/* TOGGLE MENU */
.menu-toggle {
  display: none;
  font-size: 28px;
  cursor: pointer;
  color: white;
  position: absolute;
  top: 18px;
  right: 20px;
  z-index: 1001;
}

/* =========================================
   DETAIL CONTAINER (Desain Dua Kolom)
========================================= */
.detail-container {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  max-width: 1500px;
  margin: 60px auto;
  padding: 40px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  gap: 30px;
}

/* BAGIAN KIRI */
.detail-left {
  width: 30%;
  /* display: flex; */
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.book-cover-section {
  width: 100%;
  display: flex;
  justify-content: center;
}

.book-cover {
  width: 100%;
  max-width: 220px;
  border-radius: 15px;
  object-fit: cover;
  background-color: #1c5092;
  box-shadow: 0 0 8px rgba(0, 0, 0, 0.2);
}

/* ISBN & AUTHORS */
.book-isbn {
  margin-top: 20px;
  font-weight: 600;
  color: #000;
  text-align: center;
}

.book-authors {
  margin-top: 15px;
}

.book-authors p {
  margin: 4px 0;
  font-size: 14px;
}

/* GARIS PEMISAH */
.detail-divider {
  width: 2px;
  background-color: #000;
  height: auto;
  align-self: stretch;
}

/* BAGIAN KANAN */
.detail-right {
  width: 68%;
}

.book-title {
  color: #000;
  font-size: 26px;
  font-weight: 700;
  margin-bottom: 20px;
  text-align: left;
}

.book-abstract h2 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.book-abstract p {
  font-size: 15px;
  line-height: 1.7;
  text-align: justify;
}

/* TOMBOL DOWNLOAD */
.download-section {
  margin-top: 25px;
  display: flex;
  justify-content: center;
  gap: 15px;
}

.download-section .btn {
  font-size: 14px;
  padding: 10px 18px;
  width: 20pc;
}

/* =========================================
   BUTTON STYLING
========================================= */
.btn {
  background-color: #002b7a;
  color: white;
  padding: 10px 20px;
  text-decoration: none;
  border-radius: 5px;
  font-size: 14px;
  transition: background-color 0.3s ease;
  text-align: center;
}

.btn:hover {
  background-color: #001d52;
}

.btn-secondary {
  background-color: #0056b3;
}

.btn-secondary:hover {
  background-color: #003d80;
}

/* =========================================
   FOOTER
========================================= */
.footer {
  background-color: #000;
  color: white;
  padding: 40px 20px 20px;
  font-size: 14px;
}

.footer-container {
  display: flex;
  flex-wrap: wrap;
  gap: 40px;
  justify-content: space-between;
  max-width: 1200px;
  margin: auto;
}

.footer-section {
  flex: 1;
  min-width: 220px;
}

.footer-logo {
  width: 180px;
  margin-bottom: 10px;
}

.footer-section h4 {
  font-size: 16px;
  margin-bottom: 10px;
  border-bottom: 2px solid #007bff;
  display: inline-block;
  padding-bottom: 5px;
}

.footer-section ul {
  list-style: none;
  padding: 0;
}

.footer-section ul li {
  margin-bottom: 8px;
}

.footer-section ul li a {
  color: white;
  text-decoration: none;
}

.footer-section ul li a:hover {
  text-decoration: underline;
}

.footer-bottom {
  text-align: center;
  border-top: 1px solid #444;
  margin-top: 40px;
  padding-top: 15px;
  font-size: 13px;
  color: #aaa;
}

/* =========================================
   RESPONSIVE TABLET & MOBILE
========================================= */
@media (max-width: 768px) {
  /* NAVBAR */
  .navbar {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav-links {
    display: none;
    flex-direction: column;
    width: 100%;
    background-color: #1c5092;
    margin-top: 10px;
    padding: 10px 0;
  }

  .nav-links.show {
    display: flex;
  }

  .nav-links li {
    text-align: center;
    padding: 10px 20px;
  }

  .menu-toggle {
    display: block;
  }

  /* DETAIL CONTAINER RESPONSIVE */
  .detail-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 25px 15px;
    margin: 20px 10px;
  }

  .detail-divider {
    display: none;
  }

  .detail-left,
  .detail-right {
    width: 100%;
  }

  /* Cover dan data di tengah */
  .detail-left {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
  }

  .book-cover-section {
    justify-content: center;
    margin-bottom: 15px;
  }

  .book-cover {
    max-width: 200px;
  }

  .book-isbn {
    margin-top: 15px;
    font-size: 15px;
    text-align: center;
    width: 100%;
  }

  .book-authors {
    margin-top: 10px;
    width: 100%;
    text-align: center;
  }

  .book-authors p {
    font-size: 14px;
    margin: 3px 0;
  }

  /* Judul & sinopsis */
  .book-title {
    text-align: center;
    font-size: 22px;
  }

  .book-abstract h2 {
    text-align: left;
    font-size: 16px;
    margin-top: 10px;
  }

  .book-abstract p {
    font-size: 14px;
    line-height: 1.6;
    text-align: justify;
  }

  /* Tombol */
  .download-section {
    justify-content: center;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    width: 100%;
  }

  .btn {
    width: 90%;
    font-size: 15px;
  }
}

@media (max-width: 480px) {
  .book-title {
    font-size: 20px;
  }

  .book-cover {
    max-width: 160px;
  }

  .book-abstract p {
    font-size: 13px;
  }

  .btn {
    font-size: 14px;
    padding: 10px;
    width: 100%;
  }
}