/*
  Zentrales Stylesheet – bewusst leichtgewichtig, damit die Landingpage ohne Framework performant bleibt.
  Kommentare erklären zentrale Regeln, sodass auch Einsteiger:innen Anpassungen nachvollziehen können.
*/

:root {
  /* Grundfarbpalette: hohe Kontraste für Lesbarkeit, dezente Akzente für Buttons. */
  --color-bg: #f7f8fb;
  --color-surface: #ffffff;
  --color-text: #1c2534;
  --color-muted: #5b6474;
  --color-accent: #175cd3;
  --color-accent-light: #e7f0ff;
  --color-border: #d8dee6;
  --color-success: #117d3e;

  --font-base: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --radius-md: 12px;
  --shadow-sm: 0 10px 25px rgba(28, 37, 52, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth; /* Angenehmes Scrollen bei internen Links. */
}

body {
  margin: 0;
  font-family: var(--font-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}

a:hover,
a:focus {
  text-decoration: underline;
}

/* Skip-Link bleibt unsichtbar, bis er fokussiert wird – wichtig für Tastaturnutzer:innen. */
.skip-link {
  position: absolute;
  top: -40px;
  left: 16px;
  padding: 8px 12px;
  background: var(--color-accent);
  color: #ffffff;
  border-radius: 6px;
  z-index: 1000;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  background: linear-gradient(135deg, #0f172a, #1d293f);
  color: #ffffff;
  padding: 24px;
  position: sticky;
  top: 0;
  z-index: 999;
}

/* Hero-Bereich liegt unterhalb des Headers und behält denselben Look & Feel. */
.hero-section {
  background: linear-gradient(135deg, #0f172a, #1d293f);
  color: #ffffff;
  padding: 48px 24px 72px 24px;
}

.top-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1100px;
  margin: 0 auto 24px auto;
}

.logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: #ffffff;
}

.nav-links {
  display: flex;
  gap: 16px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: #e2e8f0;
  font-weight: 500;
}

.hero {
  max-width: 1100px;
  margin: 0 auto;
  padding-bottom: 16px;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: #dbeafe;
}

.hero-meta {
  font-size: 0.95rem;
  color: #cbd5f5;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--color-accent);
  color: #ffffff;
  font-weight: 600;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.button:hover,
.button:focus {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(23, 92, 211, 0.25);
}

.button-secondary {
  background: transparent;
  border: 1px solid rgba(226, 232, 240, 0.8);
  color: #e2e8f0;
}

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 32px 24px 80px 24px;
}

.section {
  margin-bottom: 72px;
}

.section-header h2 {
  margin-bottom: 8px;
}

.section-header p {
  margin-top: 0;
  color: var(--color-muted);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
}

.card h3 {
  margin-top: 0;
  font-size: 1.1rem;
}

.filter-form {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  background: var(--color-surface);
  padding: 20px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
}

.filter-group {
  display: flex;
  flex-direction: column;
  min-width: 180px;
}

.filter-group label {
  font-weight: 600;
  margin-bottom: 4px;
}

.filter-group select,
.filter-group input[type="range"] {
  padding: 8px;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  font-size: 1rem;
}

.filter-count {
  margin-top: 12px;
  font-weight: 600;
  color: var(--color-muted);
}

.table-wrapper {
  overflow-x: auto; /* Ermöglicht horizontales Scrollen auf kleinen Bildschirmen. */
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 960px; /* Verhindert zu starke Verengung bei vielen Spalten. */
}

table caption {
  caption-side: top;
  padding: 16px;
  font-weight: 700;
  font-size: 1.05rem;
  text-align: left;
}

thead th {
  background: var(--color-accent-light);
  padding: 12px;
  text-align: left;
  font-size: 0.95rem;
}

tbody td {
  padding: 12px;
  border-top: 1px solid var(--color-border);
  font-size: 0.92rem;
}

.table-note {
  margin-top: 12px;
  color: var(--color-muted);
  font-style: italic;
}

.profile {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 24px;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.criteria-list {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: 24px;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.method-note {
  margin-top: 24px;
  padding: 20px;
  border-left: 4px solid var(--color-accent);
  background: var(--color-accent-light);
}

.team-section {
  margin-top: 24px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: 18px;
}

.faq-list details {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: 16px 20px;
  margin-bottom: 12px;
  box-shadow: var(--shadow-sm);
}

.faq-list summary {
  cursor: pointer;
  font-weight: 600;
}

.download-list {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.download-list a {
  padding: 8px 16px;
  border-radius: 999px;
  border: 1px solid var(--color-accent);
  color: var(--color-accent);
  font-weight: 600;
}

.cta-block {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.cta-hint {
  color: var(--color-muted);
}

.site-footer {
  background: #0f172a;
  color: #e2e8f0;
  padding: 24px;
  text-align: center;
}

.site-footer nav {
  margin-top: 12px;
  display: flex;
  justify-content: center;
  gap: 16px;
}

.site-footer a {
  color: #cbd5f5;
}

/* Utility-Klasse für Screenreader-only Texte. */
.sr-only {
  border: 0;
  clip: rect(0, 0, 0, 0);
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  width: 1px;
}

/* Mobile Optimierungen: Navigation stapeln, Polsterungen reduzieren. */
@media (max-width: 768px) {
  .top-nav {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  .nav-links {
    flex-wrap: wrap;
    gap: 10px;
  }

  main {
    padding: 24px 16px 60px 16px;
  }

  .filter-form {
    flex-direction: column;
  }

  .cta-block {
    flex-direction: column;
    align-items: flex-start;
  }
}