/* ═══════════════════════════════════════════════════════════════
   Koreanisch-Vokabel-Trainer · Modernes Design
   Automatischer Hell-/Dunkelmodus über prefers-color-scheme
   ═══════════════════════════════════════════════════════════════ */

:root {
  --bg:           #FAFAF9;
  --bg-elevated: #FFFFFF;
  --bg-subtle:   #F4F4F2;
  --border:      #E7E5E4;
  --border-strong: #D6D3D1;
  --text:        #1C1917;
  --text-muted:  #78716C;
  --text-subtle: #A8A29E;

  --primary:        #6366F1;
  --primary-hover:  #4F46E5;
  --primary-soft:   #EEF2FF;
  --primary-text:   #FFFFFF;

  --accent:        #F59E0B;
  --accent-soft:   #FEF3C7;

  --success:       #10B981;
  --success-soft:  #D1FAE5;
  --danger:        #EF4444;
  --danger-soft:   #FEE2E2;

  --shadow-sm: 0 1px 2px rgba(0,0,0,.04), 0 1px 1px rgba(0,0,0,.03);
  --shadow-md: 0 4px 12px rgba(0,0,0,.06), 0 1px 3px rgba(0,0,0,.04);
  --shadow-lg: 0 10px 30px rgba(0,0,0,.08), 0 2px 8px rgba(0,0,0,.04);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 22px;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-8: 48px;

  --font-ui: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  /* Koreanische Schrift für Hangul-Anzeige */
  --font-ko: 'Noto Sans KR', 'Malgun Gothic', 'Apple SD Gothic Neo', sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:           #0B0B0F;
    --bg-elevated:  #17171D;
    --bg-subtle:    #1F1F26;
    --border:       #2A2A33;
    --border-strong: #3A3A47;
    --text:         #FAFAF9;
    --text-muted:   #A8A29E;
    --text-subtle:  #78716C;

    --primary:        #818CF8;
    --primary-hover:  #A5B4FC;
    --primary-soft:   #1E1B4B;
    --primary-text:   #0B0B0F;

    --accent:        #FBBF24;
    --accent-soft:   #422006;

    --success:       #34D399;
    --success-soft:  #064E3B;
    --danger:        #F87171;
    --danger-soft:   #7F1D1D;

    --shadow-sm: 0 1px 2px rgba(0,0,0,.4);
    --shadow-md: 0 4px 14px rgba(0,0,0,.5);
    --shadow-lg: 0 12px 36px rgba(0,0,0,.6);
  }
}

*, *::before, *::after { box-sizing: border-box; }
html, body {
  margin: 0; padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.55;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text);
  margin: 0 0 var(--space-4);
}
h1 { font-size: 32px; line-height: 1.15; }
h2 { font-size: 22px; line-height: 1.25; }
h3 { font-size: 17px; line-height: 1.3; color: var(--text); }
p  { margin: 0 0 var(--space-4); color: var(--text); }
a  { color: var(--primary); text-decoration: none; transition: color .15s; }
a:hover { color: var(--primary-hover); text-decoration: underline; text-underline-offset: 2px; }

.meta {
  font-size: 13px;
  color: var(--text-muted);
}

.hangul { font-family: var(--font-ko); }

.header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  padding: var(--space-4) var(--space-5);
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: saturate(180%) blur(10px);
  -webkit-backdrop-filter: saturate(180%) blur(10px);
}
.header-inner {
  max-width: 1080px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--space-4);
}
.brand {
  display: flex; align-items: center; gap: var(--space-3);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--text);
}
.brand-logo {
  width: 32px; height: 32px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), #8B5CF6);
  color: #FFFFFF;
  display: grid; place-items: center;
  font-weight: 700; font-size: 13px;
  box-shadow: var(--shadow-sm);
}
.nav {
  display: flex; gap: var(--space-1); flex-wrap: wrap;
}
.nav a {
  font-size: 14px;
  color: var(--text-muted);
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-md);
  transition: background .15s, color .15s;
}
.nav a:hover {
  background: var(--bg-subtle);
  color: var(--text);
  text-decoration: none;
}
.nav a.active {
  background: var(--primary-soft);
  color: var(--primary);
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: var(--space-6) var(--space-5);
}

.statusbar {
  border-top: 1px solid var(--border);
  padding: var(--space-4) var(--space-5);
  font-size: 12px;
  color: var(--text-subtle);
  text-align: center;
  margin-top: var(--space-8);
}

.panel {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin-bottom: var(--space-4);
  box-shadow: var(--shadow-sm);
}
.panel-accent {
  background: linear-gradient(135deg, var(--primary-soft), var(--bg-elevated));
  border-color: var(--border);
}

.btn {
  display: inline-flex;
  align-items: center; justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  cursor: pointer;
  text-decoration: none;
  transition: all .15s ease;
  user-select: none;
  white-space: nowrap;
}
.btn:hover {
  background: var(--bg-subtle);
  border-color: var(--text-subtle);
  text-decoration: none;
  transform: translateY(-1px);
}
.btn:active { transform: translateY(0); }
.btn:disabled, .btn[disabled] {
  background: var(--bg-subtle);
  border-color: var(--border);
  color: var(--text-subtle);
  cursor: not-allowed;
  transform: none;
}

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

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

.btn-accent {
  background: var(--accent);
  color: #1C1917;
  border-color: var(--accent);
}
.btn-accent:hover {
  filter: brightness(1.05);
  color: #1C1917;
}

.btn-correct {
  background: var(--success);
  color: #FFFFFF;
  border-color: var(--success);
}
.btn-correct:hover { filter: brightness(1.05); color: #FFFFFF; }

.btn-wrong {
  background: var(--danger);
  color: #FFFFFF;
  border-color: var(--danger);
}
.btn-wrong:hover { filter: brightness(1.05); color: #FFFFFF; }

.btn-row {
  display: flex; flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.icon-btn {
  width: 36px; height: 36px;
  padding: 0;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 50%;
  cursor: pointer;
  color: var(--text-muted);
  transition: all .15s ease;
}
.icon-btn:hover {
  background: var(--primary-soft);
  color: var(--primary);
  border-color: var(--primary);
}
.icon-btn svg { width: 18px; height: 18px; }

input[type="text"], input[type="password"], select, textarea {
  font-family: inherit;
  font-size: 15px;
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  width: 100%;
  transition: border-color .15s, box-shadow .15s;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-soft);
}
label {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  display: block;
  margin-bottom: 6px;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
thead th {
  background: var(--bg-subtle);
  color: var(--text-muted);
  font-weight: 500;
  text-align: left;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  position: sticky; top: 0;
}
tbody td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
tbody tr:hover { background: var(--bg-subtle); }
tbody tr:last-child td { border-bottom: none; }

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}
.stat-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  transition: transform .15s, box-shadow .15s;
}
.stat-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.stat-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}
.stat-num.accent { color: var(--primary); }
.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 500;
}

.progress-bar {
  background: var(--bg-subtle);
  border-radius: 999px;
  height: 8px;
  overflow: hidden;
}
.progress-bar > span {
  display: block; height: 100%;
  background: linear-gradient(90deg, var(--primary), #8B5CF6);
  border-radius: 999px;
  transition: width .3s ease;
}

.mastery {
  display: inline-flex;
  gap: 2px;
  color: var(--accent);
  font-size: 13px;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 9px;
  font-size: 11px;
  font-weight: 500;
  color: var(--text-muted);
  background: var(--bg-subtle);
  border-radius: 999px;
  letter-spacing: 0.02em;
}
.badge-TOPIK1 { background: #DCFCE7; color: #166534; }
.badge-TOPIK2 { background: #DBEAFE; color: #1E40AF; }
.badge-TOPIK3 { background: #FEF3C7; color: #92400E; }
@media (prefers-color-scheme: dark) {
  .badge-TOPIK1 { background: #14532D; color: #BBF7D0; }
  .badge-TOPIK2 { background: #1E3A8A; color: #BFDBFE; }
  .badge-TOPIK3 { background: #78350F; color: #FDE68A; }
}

.card-stage {
  display: flex; justify-content: center;
  padding: var(--space-5) 0;
}
.flashcard {
  width: 100%; max-width: 560px;
  min-height: 280px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  text-align: center;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: var(--space-3);
  user-select: none;
  position: relative;
  transition: transform .15s, box-shadow .2s;
}
.flashcard:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}
.flashcard .word {
  font-size: 44px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.03em;
  margin: 0;
  line-height: 1.1;
  font-family: var(--font-ko);
}
.flashcard .word.de {
  font-family: var(--font-ui);
}
.flashcard .rom {
  font-size: 18px;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.01em;
  margin-top: 4px;
}
.flashcard .pos {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
  text-transform: lowercase;
  letter-spacing: 0.04em;
}
.flashcard .example {
  font-size: 15px;
  color: var(--text-muted);
  font-style: italic;
  margin-top: var(--space-2);
  line-height: 1.5;
  max-width: 420px;
}
.flashcard .example.ko { font-family: var(--font-ko); font-style: normal; }
.flashcard .hint {
  position: absolute; bottom: 14px; left: 50%;
  transform: translateX(-50%);
  font-size: 11px;
  color: var(--text-subtle);
  font-weight: 500;
  letter-spacing: 0.02em;
}
.speak-btn {
  position: absolute; top: 16px; right: 16px;
}

.mcq-options {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2);
  max-width: 560px;
  margin: 0 auto;
}
.mcq-options button {
  font-size: 15px;
  padding: 14px 20px;
  text-align: left;
  font-weight: 500;
}
.mcq-options button.correct {
  background: var(--success);
  color: #FFFFFF !important;
  border-color: var(--success);
}
.mcq-options button.wrong {
  background: var(--danger);
  color: #FFFFFF !important;
  border-color: var(--danger);
}

.typing-input {
  font-size: 22px;
  text-align: center;
  padding: 14px 18px;
  font-weight: 500;
}
.typing-input.ko { font-family: var(--font-ko); }
.typing-row {
  display: flex;
  gap: 8px;
  align-items: center;
}
.typing-row .typing-input { flex: 1; }

.feedback-correct { color: var(--success); font-weight: 600; }
.feedback-wrong   { color: var(--danger);  font-weight: 600; }

.alert {
  background: var(--primary-soft);
  border: 1px solid var(--primary);
  color: var(--primary);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  font-size: 14px;
}
.alert-error {
  background: var(--danger-soft);
  border-color: var(--danger);
  color: var(--danger);
}
.alert-info {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: #92400E;
}
@media (prefers-color-scheme: dark) {
  .alert-info { color: #FDE68A; }
}

.progress-counter {
  display: flex; justify-content: center; align-items: center;
  gap: var(--space-3);
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: var(--space-3);
}
.progress-counter strong { color: var(--text); font-weight: 600; }

@media (max-width: 640px) {
  .header { padding: var(--space-3) var(--space-4); }
  .header-inner { gap: var(--space-2); }
  .nav a { padding: 6px 10px; font-size: 13px; }
  .container { padding: var(--space-4) var(--space-3); }
  .panel { padding: var(--space-4); border-radius: var(--radius-md); }
  .flashcard {
    padding: var(--space-5);
    min-height: 240px;
    border-radius: var(--radius-lg);
  }
  .flashcard .word { font-size: 34px; }
  .flashcard .rom { font-size: 15px; }
  h1 { font-size: 26px; }
  .stat-num { font-size: 26px; }
  table { font-size: 13px; }
  thead th, tbody td { padding: 8px 10px; }
}

.login-wrap {
  min-height: 80vh;
  display: flex; align-items: center; justify-content: center;
  padding: var(--space-5);
}
.login-box {
  width: 100%; max-width: 400px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-lg);
}
.login-box .brand-logo {
  width: 48px; height: 48px;
  margin: 0 auto var(--space-3);
  font-size: 18px;
  border-radius: 14px;
}
.login-box h1 {
  font-size: 24px;
  text-align: center;
  margin-bottom: var(--space-2);
}
.login-box p.meta {
  text-align: center;
  margin-bottom: var(--space-5);
}

.icon { display: inline-block; vertical-align: middle; }

.toolbar {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-3);
}
.toggle-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  transition: all .15s;
  user-select: none;
}
.toggle-pill:hover { border-color: var(--primary); color: var(--text); }
.toggle-pill input[type="checkbox"] {
  width: auto;
  margin: 0;
  accent-color: var(--primary);
}
.toggle-pill:has(input:checked) {
  background: var(--primary-soft);
  border-color: var(--primary);
  color: var(--primary);
}

.rev-cell { cursor: default; }
.rev-masked { display: none; }
table.learn-mode .rev-cell { cursor: pointer; }
table.learn-mode .rev-cell .rev-content { display: none; }
table.learn-mode .rev-cell .rev-masked {
  display: block;
  color: var(--accent);
  font-size: 16px;
  letter-spacing: 4px;
  padding: 4px 0;
  user-select: none;
}
table.learn-mode .rev-cell:hover .rev-masked { opacity: .7; }
table.learn-mode .rev-cell.revealed .rev-content { display: block; }
table.learn-mode .rev-cell.revealed .rev-masked { display: none; }

/* Voice-Selector im Header */
.voice-select {
  display: inline-flex;
  gap: 2px;
  background: var(--bg-subtle);
  padding: 3px;
  border-radius: 999px;
  border: 1px solid var(--border);
}
.voice-select button {
  background: transparent;
  border: none;
  padding: 4px 10px;
  border-radius: 999px;
  cursor: pointer;
  font-size: 12px;
  color: var(--text-muted);
  font-family: inherit;
  font-weight: 500;
}
.voice-select button.active {
  background: var(--bg-elevated);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}