:root {
  --primary-color: #2d6cdf;
  --background-color: #f5f7fa;
  --surface-color: #ffffff;
  --text-primary: #1a1a1a;
  --text-secondary: #4a4a4a;
  --border-color: #d5dae0;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --radius-sm: 4px;
  --radius-md: 8px;
  --font-base: system-ui, sans-serif;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 8px rgba(0,0,0,0.08);
  --breakpoint-md: 640px;
  --breakpoint-lg: 1024px;
}

body {
  margin: 0;
  font-family: var(--font-base);
  background-color: var(--background-color);
  color: var(--text-primary);
  line-height: 1.5;
}

/* === App Shell === */
.app-header,
.app-footer {
  background-color: var(--surface-color);
  border-bottom: 1px solid var(--border-color);
  padding: var(--spacing-sm) var(--spacing-lg);
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.app-main {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.dashboard-section {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
}

.sidebar {
  background-color: var(--surface-color);
  border-right: 1px solid var(--border-color);
  padding: var(--spacing-md);
}

@media (min-width: var(--breakpoint-lg)) {
  .dashboard-section {
    grid-template-columns: 280px 1fr;
  }
}

.app-footer {
  border-top: 1px solid var(--border-color);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: var(--spacing-sm);
}

/* === Summary Cards === */
.summary-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.summary-cards .card {
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-md);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.summary-cards .card-title {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xs);
}

.summary-cards .card-value {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--primary-color);
}

/* === Chart Panel === */
.chart-panel {
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-md);
  min-height: 280px;
  display: flex;
  flex-direction: column;
}

.chart-panel__header {
  font-weight: 500;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.chart-panel__body {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* === Filter Panel === */
.filter-panel {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: var(--spacing-sm);
  box-shadow: var(--shadow-sm);
}

.filter-panel label {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.filter-panel select,
.filter-panel input {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 0.4rem 0.6rem;
  font-family: var(--font-base);
}

.filter-panel button {
  background-color: var(--primary-color);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  padding: 0.5rem 1rem;
  cursor: pointer;
}

.filter-panel button:hover {
  opacity: 0.9;
}

@media (min-width: var(--breakpoint-md)) {
  .filter-panel {
    justify-content: flex-start;
  }
}

/* === Footer Copyright === */
.app-footer small {
  display: block;
  margin-top: var(--spacing-xs);
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.app-footer small::after {
  content: " © 2026 Donau2Space.de";
}