/* Общие стили */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  background: #f9f9f9;
  color: #333;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header {
  background: #2c3e50;
  padding: 1rem 2rem;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: #ecf0f1;
  text-decoration: none;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

nav ul li a {
  color: #ecf0f1;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

nav ul li a:hover {
  color: #f1c40f;
}

main {
  flex: 1;
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

h1, h2 {
  color: #2c3e50;
  margin-bottom: 1rem;
}

h2 {
  font-size: 2rem;
  text-align: center;
}

/* Главная */
.hero {
  text-align: center;
  padding: 4rem 1rem;
  background: linear-gradient(135deg, #3498db, #2ecc71);
  color: white;
  border-radius: 12px;
  margin-bottom: 3rem;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
  color: white;
}

.hero p {
  font-size: 1.3rem;
  max-width: 700px;
  margin: 0 auto 1.5rem;
}

.btn {
  display: inline-block;
  background: #f1c40f;
  color: #2c3e50;
  padding: 0.8rem 2.5rem;
  border-radius: 30px;
  text-decoration: none;
  font-weight: bold;
  transition: background 0.3s;
}

.btn:hover {
  background: #e67e22;
}

.cards {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
  margin-top: 2rem;
}

.card {
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  flex: 1 1 250px;
  max-width: 300px;
  text-align: center;
}

.card h3 {
  margin-bottom: 0.5rem;
  color: #2c3e50;
}

/* Каталог */
.book-list {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
  margin-top: 2rem;
}

.book-item {
  background: white;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  padding: 1.5rem;
  width: 220px;
  text-align: center;
  transition: transform 0.2s;
}

.book-item:hover {
  transform: translateY(-5px);
}

.book-item img {
  width: 100%;
  height: auto;
  border-radius: 8px;
  margin-bottom: 0.8rem;
}

.book-item h3 {
  font-size: 1.1rem;
  margin-bottom: 0.2rem;
}

.book-item .author {
  font-style: italic;
  color: #7f8c8d;
  font-size: 0.9rem;
}

.book-item .desc {
  font-size: 0.9rem;
  margin: 0.8rem 0;
}

.btn-small {
  display: inline-block;
  background: #3498db;
  color: white;
  padding: 0.4rem 1.2rem;
  border-radius: 20px;
  text-decoration: none;
  font-size: 0.9rem;
  transition: background 0.3s;
}

.btn-small:hover {
  background: #2980b9;
}

/* Деталь книги */
.book-detail {
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.book-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  margin-top: 1.5rem;
}

.book-meta img {
  flex: 0 0 300px;
  max-width: 100%;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

.book-meta .info {
  flex: 1;
}

.book-meta .info p {
  margin-bottom: 0.8rem;
}

/* О проекте */
.about {
  background: white;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  max-width: 800px;
  margin: 0 auto;
}

.about p {
  margin-bottom: 1rem;
}

/* Футер */
footer {
  background: #2c3e50;
  color: #ecf0f1;
  text-align: center;
  padding: 1rem 0;
  margin-top: 2rem;
}

/* Адаптив */
@media (max-width: 768px) {
  nav {
    flex-direction: column;
    gap: 0.5rem;
  }
  .hero h1 {
    font-size: 2rem;
  }
  .book-meta {
    flex-direction: column;
  }
  .book-meta img {
    flex: 1 1 100%;
  }
}