* {
  box-sizing: border-box;
  scroll-behavior: smooth;
}

html, body {
  height: 100%;
  margin: 0;
  font-family: "Merriweather", "Georgia", serif;
  color: #1c2e2d;
  background: #ffffff;
  line-height: 1.8;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

/* ====== Header ====== */
/* ===== HEADER ===== */
.site-header {
  position: fixed;
  top: 0;
  width: 100%;
  height: 80px;
  background: #000; /* solid black */
  box-shadow: 0 4px 15px rgba(0,0,0,0.15);
  z-index: 1000;
}

/* overlay behind header content */
.site-header::after {
  content: '';
  position: absolute;
  top:0; left:0;
  width:100%; height:100%;
  background: rgba(9,9,9,0.274);
  pointer-events: none; /* important: clicks pass through */
  z-index: 0;
}

/* header content container */
.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  position: relative;
  z-index: 10; /* ensure it's above overlay */
}

/* Logo */
.logo {
  font-family: "Playfair Display", serif;
  font-size: 2rem;
  color: #fff;
  margin: 0;
  letter-spacing: 0.5px;
  margin-left: -3.5rem;
}

/* Nav */
.nav {
  display: flex;
  gap: 1.5rem;
  z-index: 10; /* above overlay */
}

.nav a {
  text-decoration: none;
  font-weight: 600;
  color: #e4f2ec;
  position: relative;
  transition: all 0.3s ease;
}

.nav a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  left: 0;
  bottom: -4px;
  background: #b6d226;
  transition: width 0.3s;
}

.nav a:hover::after,
.nav a.active::after {
  width: 100%;
}

.nav a:hover,
.nav a.active {
  color: #fbbc0e;
  text-shadow: 0 0 6px #4ec292,0 0 12px #028e8c;
}

/* Hamburger button */
.menu-toggle {
  display: none; /* hidden on desktop */
  background: none;
  border: none;
  font-size: 2.5rem;
  color: #e4f2ec;
  cursor: pointer;
  position: relative;
  z-index: 20; /* above overlay & nav */
}

/* ===== RESPONSIVE MOBILE ===== */
@media (max-width: 768px) {
  /* show hamburger */
  .menu-toggle {
    display: block;
  }

  /* hide nav by default */
  .nav {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 100%;
    right: 0;
    width: 100%;
    background: #303332;
    padding: 1rem 0;
    z-index: 15; /* below hamburger but above overlay */
  }

  /* show nav when toggled */
  .nav.show {
    display: flex;
  }

  .nav a {
    margin: 1rem 0;
    text-align: center;
  }
}

/* ===== BOOK SECTION ===== */
.book-section {
  background: #f9f9f9;
  padding: 5rem 0;
}
.container {
  width: 90%;
  max-width: 1100px;
  margin: 0 auto;
}
.section-title {
  text-align: center;
  font-size: 2rem;
  margin-top: 1rem;
  color: #222;
  position: relative;
}
.section-title::after {
  content: "";
  display: block;
  width: 80px;
  height: 4px;
  background: #ffcc00;
  margin: 1rem auto 0;
  border-radius: 4px;
}
.book-card {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2rem;
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
  padding: 2rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.book-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.15);
}
.book-card img {
  width: 280px;
  border-radius: 12px;
  object-fit: cover;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s ease;
}
.book-card img:hover {
  transform: scale(1.03);
}
.book-info {
  flex: 1;
}
.book-info h3 {
  font-size: 1.8rem;
  color: #111;
  margin-bottom: 1rem;
}
.book-info p {
  color: #444;
  line-height: 1.6;
  margin-bottom: 1rem;
}
.book-info ul {
  margin: 1rem 0;
  padding-left: 1.2rem;
  color: #333;
}
.book-info li {
  margin-bottom: 0.4rem;
}
.btn {
  background: #ffcc00;
  color: #000;
  padding: 10px 24px;
  border-radius: 30px;
  text-decoration: none;
  font-weight: 600;
  display: inline-block;
  transition: all 0.3s ease;
}
.btn:hover {
  background: #111;
  color: #fff;
  transform: scale(1.05);
}

/* ===== FOOTER ===== */
footer {
  background: #0b2f23;
  color: #ccc;
  text-align: center;
  padding: 1.5rem 0;
  margin-top: 3rem;
}
footer p {
  margin: 0;
  font-size: 0.95rem;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .book-card {
    flex-direction: column;
    text-align: center;
  }
  .book-card img {
    width: 80%;
    max-width: 280px;
  }
}