/* ============================================================
   Leichte Sprache — Studierendenwerk Saarland
   Design-System: WCAG 2.1 AA, Iframe-kompatibel
   Font: Atkinson Hyperlegible (Google Fonts)
   ============================================================ */

/* --- Design-Token --- */
:root {
  --color-primary:       #01569A;
  --color-primary-dark:  #014080;
  --color-primary-light: #E0F0FB;
  --color-accent:        #E87722;
  --color-accent-dark:   #C0601A;
  --color-text:          #1A1A1A;
  --color-text-muted:    #595959;
  --color-bg:            #FFFFFF;
  --color-bg-alt:        #F4F8FB;
  --color-border:        #C8DCEA;
  --color-separator:     #D0E4F0;
  --color-focus:         #E87722;
  --color-nav-bg:        #005B8E;
  --color-nav-text:      #FFFFFF;
  --color-nav-active:    #E87722;
  --color-card-hover:    #003F63;

  --font-base:    'Atkinson Hyperlegible', Arial, Helvetica, sans-serif;
  --size-base:    1.25rem;     /* 20px */
  --size-h1:      2rem;        /* 32px */
  --size-h2:      1.625rem;    /* 26px */
  --size-h3:      1.375rem;    /* 22px */
  --size-small:   1rem;        /* 16px */
  --lh-base:      1.75;
  --lh-heading:   1.3;

  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-12: 3rem;
  --space-16: 4rem;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  --max-content: 1200px;
  --shadow-card: 0 2px 8px rgba(0, 91, 142, 0.12);
  --shadow-card-hover: 0 4px 16px rgba(0, 91, 142, 0.22);
}

/* --- Reset & Basis --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-base);
  font-size: var(--size-base);
  line-height: var(--lh-base);
  color: var(--color-text);
  background: var(--color-bg);
  /* KEIN overflow: hidden — Iframe-Kompatibilität */
}

/* --- Skip-Link (WCAG 2.4.1) --- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: var(--space-2);
  background: var(--color-primary);
  color: #fff;
  padding: var(--space-3) var(--space-6);
  font-size: var(--size-base);
  font-weight: 700;
  text-decoration: none;
  border-radius: var(--radius-sm);
  z-index: 9999;
}
.skip-link:focus {
  left: var(--space-4);
}

/* --- Fokus-Ring (WCAG 2.4.7) --- */
:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* --- Header --- */
.site-header {
  background: #ffffff;
  color: var(--color-primary);
  padding: var(--space-6) var(--space-8);
  display: flex;
  align-items: center;
  gap: var(--space-6);
  border-bottom: 1px solid var(--color-border);
}

.site-logo {
  height: 56px;
  width: auto;
  flex-shrink: 0;
}

.site-header__text {
  display: flex;
  flex-direction: column;
}

.site-header__subtitle {
  font-size: var(--size-small);
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.site-header__title {
  font-size: var(--size-h2);
  font-weight: 700;
  line-height: var(--lh-heading);
}

/* --- Hauptnavigation --- */
.site-nav {
  background: var(--color-primary);
  position: sticky;
  top: 0;
  z-index: 100;
  border-top: 1px solid rgba(255,255,255,0.15);
  box-shadow: 0 2px 6px rgba(0,0,0,0.18);
}

.nav-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  max-width: var(--max-content);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.nav-list a {
  display: block;
  padding: var(--space-4) var(--space-4);
  color: var(--color-nav-text);
  font-size: 0.875rem;
  font-weight: 700;
  text-decoration: none;
  border-bottom: 3px solid transparent;
  transition: background 0.15s, border-color 0.15s;
  min-height: 44px;
  display: flex;
  align-items: center;
}

.nav-list a:hover {
  background: var(--color-primary-dark);
  color: var(--color-nav-text);
  border-bottom-color: rgba(255,255,255,0.4);
}

.nav-list a[aria-current="page"],
.nav-list a.active {
  border-bottom-color: var(--color-accent);
  background: var(--color-primary-dark);
}

/* --- Hauptinhalt --- */
main {
  max-width: var(--max-content);
  margin: 0 auto;
  padding: var(--space-8) var(--space-6) var(--space-16);
}

/* --- Typografie --- */
h1 {
  font-size: var(--size-h1);
  line-height: var(--lh-heading);
  color: var(--color-primary);
  margin-bottom: var(--space-6);
  margin-top: var(--space-8);
}

h2 {
  font-size: var(--size-h2);
  line-height: var(--lh-heading);
  color: var(--color-primary);
  margin-top: var(--space-12);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-border);
  clear: both;
}

h3 {
  font-size: var(--size-h3);
  line-height: var(--lh-heading);
  color: var(--color-primary-dark);
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
  clear: both;
}

p {
  margin-bottom: var(--space-6);
  max-width: 70ch;
}

strong {
  font-weight: 700;
}

a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}
a:hover {
  color: var(--color-primary-dark);
}

/* --- Trennlinie --- */
.section-separator {
  border: none;
  border-top: 2px solid var(--color-separator);
  margin: var(--space-12) 0;
  clear: both;
}

/* --- Listen --- */
.content-list {
  margin: var(--space-4) 0 var(--space-6) var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.content-list li {
  padding-left: var(--space-2);
}

.content-list li::marker {
  color: var(--color-accent);
  font-size: 1.2em;
}

/* --- Bilder --- */
.content-image {
  float: right;
  clear: right;
  margin: var(--space-2) 0 var(--space-4) var(--space-6);
  max-width: 180px;
}

.content-image img {
  max-width: 100%;
  width: auto;
  height: auto;
  border-radius: var(--radius-md);
  display: block;
}


.content-image figcaption {
  margin-top: var(--space-2);
  font-size: var(--size-small);
  color: var(--color-text-muted);
  font-style: italic;
}

/* --- Seiten-internes Inhaltsverzeichnis --- */
.page-toc {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  margin-bottom: var(--space-8);
}

.page-toc__title {
  font-size: var(--size-small);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}

.page-toc ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.page-toc a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 700;
  font-size: var(--size-base);
}

.page-toc a:hover {
  text-decoration: underline;
}

/* --- Startseite: Kachelnavigation --- */
.welcome-section {
  margin-bottom: var(--space-12);
}

.welcome-section h1 {
  margin-top: 0;
}

.welcome-section .intro-text {
  font-size: calc(var(--size-base) + 0.125rem);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.topic-cards h2 {
  border: none;
  padding-bottom: 0;
  margin-top: 0;
}

.card-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-6);
  margin-top: var(--space-6);
}

.topic-card {
  display: flex;
  flex-direction: column;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  text-decoration: none;
  color: var(--color-text);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.2s, transform 0.15s, border-color 0.15s;
}

.topic-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
  border-color: var(--color-primary);
}

.topic-card:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
}

.topic-card__img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: var(--color-primary-light);
  padding: var(--space-3);
}

.topic-card__body {
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.topic-card__title {
  font-size: var(--size-h3);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
  line-height: var(--lh-heading);
}

.topic-card__desc {
  font-size: var(--size-small);
  color: var(--color-text-muted);
  line-height: 1.5;
  flex-grow: 1;
}

.topic-card__arrow {
  display: inline-block;
  margin-top: var(--space-4);
  font-size: var(--size-small);
  font-weight: 700;
  color: var(--color-accent);
}

/* --- Vor/Zurück-Navigation --- */
.page-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 2px solid var(--color-border);
  flex-wrap: wrap;
}

.page-nav a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-weight: 700;
  text-decoration: none;
  font-size: var(--size-base);
  min-height: 44px;
  transition: background 0.15s, color 0.15s;
}

.page-nav a:hover {
  background: var(--color-primary);
  color: #fff;
}

.page-nav__next {
  margin-left: auto;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-bg-alt);
  border-top: 2px solid var(--color-border);
  padding: var(--space-8) var(--space-6);
  text-align: center;
  font-size: var(--size-small);
  color: var(--color-text-muted);
}

.site-footer a {
  color: var(--color-primary);
  font-weight: 700;
}

/* --- Responsive --- */
@media (max-width: 640px) {
  :root {
    --size-base: 1.125rem;   /* 18px auf kleinen Screens */
    --size-h1:   1.75rem;
    --size-h2:   1.5rem;
    --size-h3:   1.25rem;
  }

  .content-image {
    float: none;
    margin: var(--space-4) auto;
    max-width: 200px;
    display: block;
  }

  .site-header {
    padding: var(--space-4) var(--space-4);
    gap: var(--space-3);
  }

  .site-logo {
    height: 40px;
  }

  main {
    padding: var(--space-6) var(--space-4) var(--space-12);
  }

  .nav-list {
    padding: 0 var(--space-2);
  }

  .nav-list a {
    padding: var(--space-3) var(--space-3);
    font-size: 0.9rem;
  }

  .card-list {
    grid-template-columns: 1fr;
  }

  .page-nav {
    flex-direction: column;
    align-items: stretch;
  }

  .page-nav__next {
    margin-left: 0;
    text-align: center;
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .topic-card { transition: none; }
  .page-nav a { transition: none; }
}