/* =========================
   Farbvariablen (CSS Custom Properties)
   ========================= */
:root {
  --color-blue: #6EC1E4;
  --color-yellow: #FFD447;
  --color-mint: #AEE6CE;
  --color-coral: #FF866E;

  --color-background: #FFF9F1;
  --color-text: #6D6A75;
  --color-blue-contrast: #404040;

  --color-primary: var(--color-yellow);
  --color-accent: var(--color-coral);
}

/* =========================
   Global Styles & Reset
   ========================= */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: "Segoe UI", sans-serif;
  background-color: var(--color-background);
  color: var(--color-text);
  line-height: 1.6;
  font-size: 16px;
}

main {
  padding: 16px;
}

ul {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
  text-indent: 0;
}

/* =========================
   Layout: Header + Navigation
   ========================= */
header {
  background-color: var(--color-blue);
  color: var(--color-blue-contrast);
  padding: 1rem 2rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  position: relative;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
}

/* Navigation Standard (Desktop) */
nav .nav-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

nav a {
  color: var(--color-blue-contrast);
  /* color: white; */
  text-decoration: none;
  font-weight: bold;
}

/* =========================
   Burger-Menü
   ========================= */

/* Burger Icon */
.burger {
  display: none;
  font-size: 2rem;
  background: none;
  border: none;
  color: var(--color-blue-contrast);
  cursor: pointer;
}

/* =========================
   Hero Section
   ========================= */
.hero {
  background-color: var(--color-mint);
  padding: 4rem 2rem;
  text-align: center;
}

.hero h1 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.2rem;
  margin-bottom: 1.5rem;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #333;
  padding: 0.8rem 1.2rem;
  border: none;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  transition: background-color 0.3s ease;
}

.btn-primary:hover {
  background-color: var(--color-accent);
  color: white;
}

/* =========================
   Buch-Portfolio mit Flexbox
   ========================= */
.book-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
  margin-top: 2rem;
}

.book-card {
  background-color: white;
  border: 2px solid var(--color-mint);
  border-radius: 12px;
  padding: 1rem;
  max-width: 250px;
  flex: 1 1 250px;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
  transition: transform 0.2s ease;
}

.book-card:hover {
  transform: scale(1.03);
}

.book-card img {
  width: 100%;
  height: auto;
  border-radius: 8px;
  object-fit: cover;
}

.book-card h3 {
  margin: 1rem 0 0.5rem;
  font-size: 1.1rem;
  text-align: center;
}

.book-card .btn-primary {
  margin-top: auto;
  font-size: 0.9rem;
}

/* Grid für Einträge */
.material-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.material-item {
  flex: 1 1 calc(50% - 1rem); /* Zweispaltig mit Abstand */
  background: #f9f9f9;
  border-radius: 8px;
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  transition: background 0.2s ease-in-out;
}

.material-item:hover {
  background: #f1f1f1;
}

.material-icon {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.material-item a {
  color: #4d3b3b;
  text-decoration: none;
  font-weight: 500;
  word-break: break-word;
}



/* =========================
   Inhaltliche Abschnitte
   ========================= */
.section {
  padding: 2rem;
}

.section h2 {
  font-size: 1.8rem;
  margin-top: 2rem;
  margin-bottom: 1rem;
}

.buchseite-container {
  padding: 2rem 1rem;
  max-width: 1200px;
  margin: 0 auto;
  font-family: "Segoe UI", sans-serif;
}

.buch-header {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  align-items: flex-start;
  margin-bottom: 3rem;
}

.buch-cover {
  width: 250px;
  border-radius: 12px;
  border: 1px solid #c5b9b9;
  box-shadow: 0 4px 10px rgba(0,0,0,0.2);
}

.buch-info {
  flex: 1;
}

.buch-info h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: #4d3b3b;
}

.buch-info p {
  font-size: 1rem;
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.kauf-links a {
  display: inline-block;
  margin-right: 1rem;
  margin-bottom: 0.5rem;
  padding: 0.75rem 1.25rem;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  font-size: 0.95rem;
}

.zusatzmaterialien h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: #4d3b3b;
}

.download-liste {
  list-style: none;
  padding: 0;
}

.download-liste li {
  margin-bottom: 0.75rem;
}

.download-liste a {
  color: #e57c50;
  text-decoration: none;
  font-weight: 500;
}

.download-liste a:hover {
  text-decoration: underline;
}

/* =========================
   Footer
   ========================= */
footer {
  text-align: center;
  padding: 1rem;
  background-color: var(--color-blue);
  color: #2b2b2b;
  font-size: 0.9rem;
}

/* =========================
   Responsive Design
   ========================= */

/* Tablets und kleinere Bildschirme */
@media (max-width: 768px) {
  .burger {
    display: block;
  }

  nav {
    width: 100%;
  }

  nav .nav-links {
    display: none;
    flex-direction: column;
    width: 100%;
    margin-top: 1rem;
    background-color: var(--color-blue);
    padding: 0;
  }

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

  nav .nav-links li {
    padding: 0.5rem 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
  }

  nav .nav-links a {
    display: block;
    width: 100%;
    color: white;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero h1 {
    font-size: 1.8rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .section {
    padding: 1.5rem;
  }

  .book-grid {
    gap: 1.5rem;
  }

  .book-card {
    max-width: 100%;
    flex: 1 1 100%;
  }

  .buch-header {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .buch-info h1 {
    font-size: 1.6rem;
  }

  .buch-info p {
    font-size: 0.95rem;
  }

  .buch-cover {
    width: 200px;
  }

  .kauf-links a {
    width: 100%;
    text-align: center;
    margin-bottom: 0.75rem;
  }

  .material-item {
    flex: 1 1 100%;
  }
}

/* Smartphones (Portrait) */
@media (max-width: 480px) {
  .hero {
    padding: 3rem 1rem;
  }

  .hero h1 {
    font-size: 1.6rem;
  }

  .btn-primary {
    padding: 0.6rem 1rem;
    font-size: 1rem;
  }

  .section h2 {
    font-size: 1.5rem;
  }
}

/* Große Bildschirme */
@media (min-width: 1024px) {
  body {
    font-size: 18px;
  }

  .hero {
    padding: 6rem 4rem;
  }

  .hero h1 {
    font-size: 2.6rem;
  }

  .section {
    max-width: 1200px;
    margin: 0 auto;
  }
}