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

body {
  font-family: 'Inter', sans-serif;
  /* background: linear-gradient(135deg, #1b1b1b, #2a2a2a); */
  /* background: url("/img/background/categories_background.png"); */
  background: url("/img/background/about_background.png");
	background-attachment: fixed; /* ← DAS ist der Held */
	background-position: center;  /* optional für zentriertes Bild */  background-size: cover;
  color: white;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.overlay {
  background-color: rgba(0, 0, 0, 0.35); /* leichter Dark Filter für bessere Lesbarkeit */
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem 3rem;
  background-color: #111;
}

.logo {
  font-size: 1.6rem;
  font-weight: 700;
}

nav a {
  margin-left: 2rem;
  text-decoration: none;
  color: #aaa;
  font-weight: 500;
  transition: 0.2s;
}

nav a:hover,
nav a.active {
  color: white;
}

main {
  padding: 3rem;
  flex-grow: 1;
}

main h1 {
  text-align: center;
  margin-bottom: 2.5rem;
  font-size: 2.4rem;
  font-weight: 600;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 1.5rem;
  max-width: 1250px;
  margin: 0 auto;
}

.category-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(6px);
  border-radius: 12px;
  padding: 2rem 1rem;
  text-align: center;
  font-size: 1.1rem;
  font-weight: 500;
  transition: 0.3s;
  cursor: pointer;
}

.category-card:hover {
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-4px);
}

.filter-bar {
  text-align: center;
  margin-bottom: 2rem;
}

.filter-bar input {
  padding: 0.8rem 1rem;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  background-color: rgba(255, 255, 255, 0.05);
  color: white;
  width: 100%;
  max-width: 400px;
  font-size: 1rem;
  backdrop-filter: blur(6px);
}

.category-card {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(10px);
  border-radius: 16px;
  overflow: hidden;
  cursor: pointer;
  transition: 0.3s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding-bottom: 1rem;
}

.category-card img {
  width: 100%;
  height: 170px;
  border-radius: 8px;
  object-fit: cover;
}

.card-content {
  padding: 1rem;
}

.category-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: #fff;
}

.category-card p {
  color: #ccc;
  font-size: 0.9rem;
}

.category-card:hover {
  transform: scale(1.03);
  background: rgba(255, 255, 255, 0.1);
}

.back-button-internal {
  margin-bottom: 1rem;
  background: none;
  border: 1px solid #fff;
  color: #fff;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  cursor: pointer;
  transition: 0.3s;
}

.back-button-internal:hover {
  background-color: rgba(255, 255, 255, 0.1);
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 0.5fr));
  gap: 1.5rem;
  margin-top: 1rem;
}

.topic-card {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(8px);
  border-radius: 12px;
  padding: 1.2rem;
  text-align: center;
  cursor: pointer;
  transition: 0.3s ease;
}

.topic-card:hover {
  background-color: rgba(255, 255, 255, 0.1);
}


footer {
  background-color: #111;
  text-align: center;
  padding: 1rem;
  font-size: 0.85rem;
  color: #888;
}