html {
  overflow-y: scroll !important;
  width: 100%;
}

body {
  margin: 0;
  font-family: sans-serif;
  background: #f5f5f5;
  display: flex;
  height: 100vh;
  width: 100%;
}

/* --- Sidebar --- */
.sidebar {
  width: 260px;
  flex-shrink: 0;
  background: #2f3542;
  color: white;
  padding-top: 20px;
  display: flex;
  flex-direction: column;
  position: relative;
}

.sidebar h2 {
  text-align: center;
  margin-bottom: 20px;
  font-size: 1.4rem;
  font-weight: 600;
}

.nav-header {
  text-align: center;
  padding: 12px 20px;
  font-size: 1.3rem;
  font-weight: 700;
  background: #2f3542;
  color: white;
  margin-bottom: 10px;
}

.nav-section {
  margin-bottom: 10px;
}

.nav-title {
  padding: 12px 20px;
  font-size: 1.1rem;
  font-weight: 600;
  background: #3d4351;
  position: relative;
}

.nav-title:hover {
  background: #4b5162;
}

/* Jahrgangsstufen immer sichtbar */
.grade {
  padding: 10px 30px;
  background: #404756;
  cursor: pointer;
  position: relative;
}

.grade:hover {
  background: #4d5566;
}

/* Untermenü (Aufgaben) - Popup rechts neben dem Eintrag */
.submenu {
  position: absolute;
  left: 100%;
  top: 0;
  min-width: 220px;
  display: flex;
  flex-direction: column;
  background: #57606f;
  border-radius: 4px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.35);
  z-index: 500;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.2s ease;
  pointer-events: none;
  white-space: nowrap;
}

.grade:hover .submenu,
.nav-title:hover .submenu {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
}

.submenu a {
  padding: 10px 20px;
  text-decoration: none;
  color: #e6e6e6;
  font-size: 0.9rem;
}

.submenu a:hover {
  background: #6c7688;
}

/* --- Main Content --- */
.content {
  flex: 1;
  padding: 40px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.title {
  margin-top: 40px;
  font-size: 2.4rem;
  font-weight: 600;
  color: #333;
  text-align: center;
}

/* Großes Logo im Hintergrund rechts */
.background-logo {
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 45vw;
  max-width: 600px;
  opacity: 0.12;
  pointer-events: none;
  z-index: 0;
}

footer {
  margin-top: auto;
  padding: 20px;
  font-size: 0.85rem;
  color: #666;
  text-align: center;
}