/* BW Lernplattform - Hauptstylesheet */
@import url('https://fonts.googleapis.com/css2?family=Roboto+Condensed:wght@300;400;600;700&family=Source+Sans+3:ital,wght@0,300;0,400;0,600;1,400&family=JetBrains+Mono:wght@400;500&display=swap');

/* ================================================
   CSS CUSTOM PROPERTIES (Design System)
   ================================================ */
:root {
  /* Farben */
  --color-bg:           #0f1114;
  --color-surface:      #1a1d21;
  --color-surface-2:    #242830;
  --color-surface-3:    #2e333d;
  --color-border:       #2e3340;
  --color-border-light: #3a4050;

  --color-primary:       #6b7355;
  --color-primary-light: #8a9470;
  --color-primary-dark:  #4d5540;

  --color-accent:        #c9a84c;
  --color-accent-light:  #e8c96a;
  --color-accent-dark:   #a88838;

  --color-text:          #e8e9eb;
  --color-text-muted:    #8b919d;
  --color-text-dim:      #5d636f;

  --color-success:  #4a9c6e;
  --color-error:    #c0392b;
  --color-warning:  #e67e22;
  --color-info:     #3498db;

  /* Typografie */
  --font-heading: 'Roboto Condensed', sans-serif;
  --font-body:    'Source Sans 3', sans-serif;
  --font-mono:    'JetBrains Mono', monospace;

  /* Abstände */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;

  /* Rahmen */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Schatten */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.5);
  --shadow-xl: 0 16px 40px rgba(0,0,0,0.6);

  /* Übergänge */
  --transition:      200ms ease;
  --transition-slow: 400ms ease;

  /* Layout */
  --sidebar-width: 280px;
  --nav-height:    60px;
  --content-max:   900px;
}

/* ================================================
   RESET & BASE
   ================================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-body);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

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

a:hover { color: var(--color-accent-light); }

img { max-width: 100%; display: block; }

ul, ol { list-style: none; }

button, input, textarea, select {
  font-family: inherit;
  font-size: inherit;
}

/* ================================================
   TYPOGRAFIE
   ================================================ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
}

h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.15rem, 2.5vw, 1.5rem); }
h4 { font-size: 1.2rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; }

p { margin-bottom: var(--space-md); }
p:last-child { margin-bottom: 0; }

code, pre {
  font-family: var(--font-mono);
  font-size: 0.875em;
}

/* ================================================
   LAYOUT - NAVIGATION (TOP BAR)
   ================================================ */
.topnav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-lg);
  z-index: 1000;
  box-shadow: var(--shadow-md);
}

.topnav__brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
}

.topnav__brand .iron-cross {
  font-size: 1.5rem;
  color: var(--color-accent);
  line-height: 1;
}

.topnav__brand:hover { color: var(--color-accent); }

.topnav__menu {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.topnav__link {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  font-family: var(--font-heading);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  transition: all var(--transition);
  white-space: nowrap;
}

.topnav__link:hover,
.topnav__link.active {
  background: var(--color-surface-2);
  color: var(--color-accent);
}

.topnav__link .nav-icon {
  font-size: 1rem;
}

.topnav__toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-text);
  cursor: pointer;
  padding: var(--space-sm);
  font-size: 1.5rem;
}

/* ================================================
   HAUPTLAYOUT
   ================================================ */
.page-wrapper {
  padding-top: var(--nav-height);
  min-height: 100vh;
}

.page-content {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-lg);
}

.page-content--wide {
  max-width: 1200px;
}

.page-content--full {
  max-width: none;
}

/* ================================================
   CARDS & PANELS
   ================================================ */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition);
}

.card:hover { box-shadow: var(--shadow-md); }

.card--accent {
  border-color: var(--color-accent);
  border-left: 3px solid var(--color-accent);
}

.card--success {
  border-color: var(--color-success);
  border-left: 3px solid var(--color-success);
}

.card--error {
  border-color: var(--color-error);
  border-left: 3px solid var(--color-error);
}

.card__header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
}

.card__title {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-text);
}

/* ================================================
   BUTTONS
   ================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius-md);
  font-family: var(--font-heading);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition);
  white-space: nowrap;
  user-select: none;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-text);
  border-color: var(--color-primary);
}

.btn--primary:hover:not(:disabled) {
  background: var(--color-primary-light);
  border-color: var(--color-primary-light);
  color: var(--color-text);
}

.btn--accent {
  background: var(--color-accent);
  color: #0f1114;
  border-color: var(--color-accent);
}

.btn--accent:hover:not(:disabled) {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
  color: #0f1114;
}

.btn--outline {
  background: transparent;
  color: var(--color-text-muted);
  border-color: var(--color-border);
}

.btn--outline:hover:not(:disabled) {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: rgba(201, 168, 76, 0.05);
}

.btn--ghost {
  background: transparent;
  color: var(--color-text-muted);
  border-color: transparent;
}

.btn--ghost:hover:not(:disabled) {
  background: var(--color-surface-2);
  color: var(--color-text);
}

.btn--success {
  background: var(--color-success);
  color: #fff;
  border-color: var(--color-success);
}

.btn--error {
  background: var(--color-error);
  color: #fff;
  border-color: var(--color-error);
}

.btn--sm {
  padding: var(--space-xs) var(--space-md);
  font-size: 0.8rem;
}

.btn--lg {
  padding: var(--space-md) var(--space-xl);
  font-size: 1rem;
}

.btn--full { width: 100%; }

.btn-group {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

/* ================================================
   BADGES & TAGS
   ================================================ */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px var(--space-sm);
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.badge--leicht  { background: rgba(74,156,110,0.2);  color: var(--color-success); }
.badge--mittel  { background: rgba(230,126,34,0.2);  color: var(--color-warning); }
.badge--schwer  { background: rgba(192,57,43,0.2);   color: var(--color-error); }
.badge--accent  { background: rgba(201,168,76,0.2);  color: var(--color-accent); }
.badge--primary { background: rgba(107,115,85,0.2);  color: var(--color-primary-light); }
.badge--info    { background: rgba(52,152,219,0.2);  color: var(--color-info); }

/* ================================================
   FORTSCHRITTSBALKEN
   ================================================ */
.progress {
  width: 100%;
  height: 6px;
  background: var(--color-surface-2);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress__bar {
  height: 100%;
  background: var(--color-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

.progress__bar--accent { background: var(--color-accent); }
.progress__bar--success { background: var(--color-success); }

.progress-labeled {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.progress-labeled .progress { flex: 1; }
.progress-labeled .progress__value {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  min-width: 35px;
  text-align: right;
}

/* ================================================
   FORMS & INPUTS
   ================================================ */
.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--color-text-muted);
  margin-bottom: var(--space-sm);
}

.form-control {
  width: 100%;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  padding: var(--space-sm) var(--space-md);
  transition: border-color var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(201,168,76,0.1);
}

select.form-control {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%238b919d' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

/* ================================================
   ALERTS & NOTIFICATIONS
   ================================================ */
.alert {
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--radius-md);
  border-left: 3px solid;
  margin-bottom: var(--space-md);
  font-size: 0.95rem;
}

.alert--success {
  background: rgba(74,156,110,0.1);
  border-color: var(--color-success);
  color: var(--color-success);
}

.alert--error {
  background: rgba(192,57,43,0.1);
  border-color: var(--color-error);
  color: var(--color-error);
}

.alert--warning {
  background: rgba(230,126,34,0.1);
  border-color: var(--color-warning);
  color: var(--color-warning);
}

.alert--info {
  background: rgba(52,152,219,0.1);
  border-color: var(--color-info);
  color: var(--color-info);
}

/* ================================================
   GRID & FLEX UTILITIES
   ================================================ */
.grid { display: grid; }
.grid--2 { grid-template-columns: repeat(2, 1fr); gap: var(--space-lg); }
.grid--3 { grid-template-columns: repeat(3, 1fr); gap: var(--space-lg); }
.grid--4 { grid-template-columns: repeat(4, 1fr); gap: var(--space-md); }

.flex { display: flex; }
.flex-center { align-items: center; justify-content: center; }
.flex-between { align-items: center; justify-content: space-between; }
.flex-wrap { flex-wrap: wrap; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

/* ================================================
   TEXT UTILITIES
   ================================================ */
.text-muted  { color: var(--color-text-muted); }
.text-accent { color: var(--color-accent); }
.text-success { color: var(--color-success); }
.text-error   { color: var(--color-error); }
.text-warning { color: var(--color-warning); }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.text-lg { font-size: 1.125rem; }
.text-center { text-align: center; }
.text-right  { text-align: right; }
.font-heading { font-family: var(--font-heading); }
.font-mono    { font-family: var(--font-mono); }
.font-bold    { font-weight: 700; }

/* ================================================
   SPACING UTILITIES
   ================================================ */
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }
.p-md  { padding: var(--space-md); }
.p-lg  { padding: var(--space-lg); }

/* ================================================
   DIVIDER
   ================================================ */
.divider {
  height: 1px;
  background: var(--color-border);
  margin: var(--space-lg) 0;
}

/* ================================================
   SKELETON LOADER
   ================================================ */
.skeleton {
  background: linear-gradient(90deg,
    var(--color-surface-2) 25%,
    var(--color-surface-3) 50%,
    var(--color-surface-2) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-loading {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ================================================
   TOOLTIP
   ================================================ */
[data-tooltip] {
  position: relative;
  cursor: help;
}

[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-surface-3);
  color: var(--color-text);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--transition);
  border: 1px solid var(--color-border);
  z-index: 100;
}

[data-tooltip]:hover::after { opacity: 1; }

/* ================================================
   DASHBOARD - SPEZIFISCH
   ================================================ */
.dashboard-header {
  background: linear-gradient(135deg, var(--color-surface) 0%, var(--color-surface-2) 100%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl) var(--space-xl);
  margin-bottom: var(--space-xl);
  position: relative;
  overflow: hidden;
}

.dashboard-header::before {
  content: '✠';
  position: absolute;
  right: var(--space-xl);
  top: 50%;
  transform: translateY(-50%);
  font-size: 6rem;
  color: var(--color-border);
  pointer-events: none;
  opacity: 0.3;
}

.dashboard-header__title {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: var(--space-xs);
}

.dashboard-header__subtitle {
  color: var(--color-text-muted);
  font-size: 1rem;
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  text-align: center;
}

.stat-card__value {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: var(--space-xs);
}

.stat-card__label {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Themen-Liste */
.topic-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.topic-item {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-md) var(--space-lg);
  text-decoration: none;
  color: var(--color-text);
  transition: all var(--transition);
}

.topic-item:hover {
  border-color: var(--color-accent);
  background: var(--color-surface-2);
  color: var(--color-text);
}

.topic-item__icon {
  font-size: 1.5rem;
  color: var(--color-accent);
  flex-shrink: 0;
  width: 36px;
  text-align: center;
}

.topic-item__info { flex: 1; min-width: 0; }

.topic-item__title {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.topic-item__meta {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-top: 2px;
}

.topic-item__progress { flex-shrink: 0; width: 120px; }

/* ================================================
   SECTION HEADINGS
   ================================================ */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-lg);
}

.section-title {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.section-title::before {
  content: '';
  display: block;
  width: 3px;
  height: 1.2em;
  background: var(--color-accent);
  border-radius: var(--radius-full);
}

/* ================================================
   MOBILE NAVIGATION
   ================================================ */
@media (max-width: 768px) {
  .topnav__toggle { display: block; }

  .topnav__menu {
    display: none;
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: var(--space-md);
    gap: var(--space-xs);
    box-shadow: var(--shadow-lg);
  }

  .topnav__menu.is-open { display: flex; }

  .topnav__link {
    justify-content: flex-start;
    padding: var(--space-md);
    width: 100%;
  }

  .grid--2, .grid--3, .grid--4 {
    grid-template-columns: 1fr;
  }

  .page-content {
    padding: var(--space-md);
  }

  .dashboard-header::before { display: none; }

  .dashboard-header {
    padding: var(--space-lg);
  }
}

@media (max-width: 480px) {
  :root { --nav-height: 56px; }

  .btn--lg {
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.9rem;
  }

  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ================================================
   SCROLLBAR STYLING
   ================================================ */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--color-bg); }
::-webkit-scrollbar-thumb {
  background: var(--color-surface-3);
  border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover { background: var(--color-primary); }

/* ================================================
   SELECTION
   ================================================ */
::selection {
  background: rgba(201,168,76,0.3);
  color: var(--color-text);
}

/* ================================================
   PRINT
   ================================================ */
@media print {
  .topnav, .no-print { display: none !important; }
  body { background: #fff; color: #000; }
  .card { border: 1px solid #ccc; box-shadow: none; }
}