/* ============================================================================
   MD3 Forms System - Globales Design-System für alle Formularfelder
   ============================================================================
   SOURCE OF TRUTH: Abgeleitet von quiz-input-group (quiz.css)
   
   Dieses System definiert ein einheitliches Form-Pattern für die gesamte
   Webapp (Login, Profil, Admin, Quiz, etc.).
   
   STRUCTURE:
   1. GLOBAL FORM SYSTEM (Base + Variants)
   2. CORPUS-SPECIFIC LAYOUTS (Legacy-Migration)
   3. CUSTOM CHECKBOX IMPLEMENTATION (Legacy)
   
   USAGE:
   - Wrapper: Jedes Feld in <div class="form-field">
   - Label: <label> oberhalb des Inputs
   - Input/Select/Textarea: Standard HTML-Elemente
   - Varianten: Container mit .form-surface/.form-panel/.form-background
   ============================================================================ */

/* ====== PART 1: GLOBAL FORM SYSTEM ====== */

/* === Form Tokens (Semantic Layer) === */
:root {
  /* Border: IMMER sichtbar, wie bei Quiz-Feldern
     Fallback-Werte für den Fall dass Tokens nicht gesetzt sind */
  --form-field-bg: var(--md-sys-color-surface-container-lowest, #fff);
  --form-field-border: var(--md-sys-color-outline-variant, #8FA9B3);  /* Deutlich sichtbares Grau */
  --form-field-border-focus: var(--md-sys-color-primary, #276D7B);    /* Primary bei Focus */
  --form-field-label: var(--md-sys-color-on-surface, #0A1F26);
  --form-field-text: var(--md-sys-color-on-surface, #0A1F26);
  --form-field-help: var(--md-sys-color-on-surface-variant, #1A3B45);
  --form-field-focus: var(--md-sys-color-primary, #276D7B);
  --form-field-error: var(--md-sys-color-error, #b3261e);
  --form-field-disabled-opacity: 0.7;
  --form-field-radius: var(--radius-md, 8px);
  --form-field-border-width: 2px;
}

/* === Base Form Structure === */
.form-field {
  display: block;
  margin-bottom: var(--space-4, 16px); /* reduziert von space-6 für dichtere Formulare */
}

.form-field:last-child {
  margin-bottom: 0;
}

.form-field > label {
  display: block;
  margin-bottom: var(--space-1, 4px); /* reduziert von space-2 für dichteres Layout */
  color: var(--form-field-label);
  font-size: 0.875rem;
  font-weight: 500; /* reduziert von 600 für weniger Dominanz */
  line-height: 1.4;
}

.form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  width: 100%;
  background: var(--form-field-bg);
  border: var(--form-field-border-width) solid var(--form-field-border);
  border-radius: var(--form-field-radius);
  padding: var(--space-4, 16px);
  color: var(--form-field-text);
  font-size: 1rem;
  font-family: inherit;
  line-height: 1.5;
  transition: border-color 150ms ease, box-shadow 150ms ease;
}

.form-field textarea {
  min-height: 100px;
  resize: vertical;
}

.form-field select {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='currentColor'%3E%3Cpath d='M7 10l5 5 5-5z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 20px 20px;
  padding-right: 44px;
}

/* === States === */
.form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea):focus {
  outline: none;
  border-color: var(--form-field-focus);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--form-field-focus) 16%, transparent); /* reduziert von 18% für subtileren Effekt */
}

.form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea):disabled {
  opacity: var(--form-field-disabled-opacity);
  cursor: not-allowed;
  background: color-mix(in srgb, var(--form-field-bg) 50%, var(--md-sys-color-surface-variant));
}

.form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea)::placeholder {
  color: var(--form-field-help);
  opacity: 0.7;
}

.form-field input:-webkit-autofill {
  -webkit-box-shadow: 0 0 0 1000px var(--form-field-bg) inset;
  -webkit-text-fill-color: var(--form-field-text);
  border-color: var(--form-field-border);
  transition: background-color 5000s ease-in-out 0s;
}

/* === Help Text === */
.form-field .help {
  display: block;
  margin-top: var(--space-1, 4px); /* reduziert von space-2 für engere Bindung */
  color: var(--form-field-help);
  font-size: 0.75rem;
  line-height: 1.35; /* leicht kompakter */
}

/* === Error State === */
.form-field.is-error > label {
  color: var(--form-field-error);
}

.form-field.is-error :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  border-color: var(--form-field-error);
}

.form-field.is-error :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea):focus {
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--form-field-error) 16%, transparent); /* reduziert von 18% für subtileren Effekt */
}

.form-field .field-error {
  display: block;
  margin-top: var(--space-1, 4px); /* reduziert von space-2 für engere Bindung */
  color: var(--form-field-error);
  font-size: 0.875rem;
  line-height: 1.35; /* leicht kompakter */
}

.form-error {
  background: var(--md-sys-color-error-container);
  color: var(--md-sys-color-on-error-container);
  border-radius: var(--form-field-radius);
  padding: var(--space-4, 16px);
  margin-bottom: var(--space-4, 16px); /* reduziert von space-6 für dichteres Layout */
  display: flex;
  gap: var(--space-3, 12px);
  align-items: flex-start;
  font-size: 0.875rem;
  line-height: 1.5;
}

.form-error .icon {
  color: var(--form-field-error);
  flex-shrink: 0;
}

/* === Hintergrund-Varianten === 
   WICHTIG: Border muss IMMER klar sichtbar sein (wie Quiz-Felder)
   Verwendet DUNKLERE Farben für maximale Sichtbarkeit auf allen Hintergründen
*/

/* Auf Cards (surface-container-lowest = weiß) */
.form-surface {
  --form-field-bg: var(--md-sys-color-surface-container-lowest, #fff);
  --form-field-border: var(--md-sys-color-outline-variant, #8FA9B3);  /* Deutlich sichtbares Grau */
}

.form-surface .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  background: var(--md-sys-color-surface-container-lowest, #fff);
  border: 2px solid var(--md-sys-color-outline-variant, #8FA9B3);
}

.form-surface .form-field :is(input, select, textarea):focus {
  border-color: var(--md-sys-color-primary, #276D7B);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--md-sys-color-primary, #276D7B) 16%, transparent);
}

/* Auf getönten Panels (surface-container-high) */
.form-panel {
  --form-field-bg: var(--md-sys-color-surface-container-lowest, #fff);
  --form-field-border: var(--md-sys-color-outline, #5A7A84);  /* Dunkler für mehr Kontrast */
}

.form-panel .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  background: var(--md-sys-color-surface-container-lowest, #fff);
  border: 2px solid var(--md-sys-color-outline, #5A7A84);
}

.form-panel .form-field :is(input, select, textarea):focus {
  border-color: var(--md-sys-color-primary, #276D7B);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--md-sys-color-primary, #276D7B) 16%, transparent);
}

/* Direkt auf Background */
.form-background {
  --form-field-bg: var(--md-sys-color-surface-container-lowest, #fff);
  --form-field-border: var(--md-sys-color-outline, #5A7A84);  /* Dunkler für Background */
}

.form-background .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  background: var(--md-sys-color-surface-container-lowest, #fff);
  border: 2px solid var(--md-sys-color-outline, #5A7A84);
}

.form-background .form-field :is(input, select, textarea):focus {
  border-color: var(--md-sys-color-primary, #276D7B);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--md-sys-color-primary, #276D7B) 16%, transparent);
}

/* In Dialogen (md3-dialog__surface = weiß) */
.form-dialog {
  --form-field-bg: var(--md-sys-color-surface-container-lowest, #fff);
  --form-field-border: var(--md-sys-color-outline-variant, #8FA9B3);  /* Deutlich sichtbares Grau */
}

.form-dialog .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  background: var(--md-sys-color-surface-container-lowest, #fff);
  border: 2px solid var(--md-sys-color-outline-variant, #8FA9B3);
}

.form-dialog .form-field :is(input, select, textarea):focus {
  border-color: var(--md-sys-color-primary, #276D7B);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--md-sys-color-primary, #276D7B) 16%, transparent);
}

/* EXPLIZITE Dialog-Regeln für garantierte Sichtbarkeit */
.md3-dialog .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea),
.md3-dialog__surface .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  background: var(--md-sys-color-surface-container-lowest, #fff);
  border: 2px solid var(--md-sys-color-outline-variant, #8FA9B3);
}

.md3-dialog .form-field :is(input, select, textarea):focus,
.md3-dialog__surface .form-field :is(input, select, textarea):focus {
  border-color: var(--md-sys-color-primary, #276D7B);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--md-sys-color-primary, #276D7B) 16%, transparent);
}

/* Dialog-Content hat bereits .md3-stack--dialog mit eigenem Gap */
.md3-dialog__content .form-field {
  margin-bottom: 0; /* Dialog-Stack übernimmt Spacing */
}

/* === Form Layout Helpers === */
.form-stack {
  display: grid;
  gap: var(--space-4, 16px);
}

.form-stack .form-field {
  margin-bottom: 0; /* Gap ersetzt margin im Stack-Kontext */
}

.form-row {
  display: grid;
  gap: var(--space-4, 16px);
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.form-field--compact {
  margin-bottom: var(--space-4, 16px);
}

.form-field--compact :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
  padding: var(--space-3, 12px);
  font-size: 0.875rem;
}

/* Modifier: Remove bottom margin for inline/toolbar usage */
.form-field--no-margin {
  margin-bottom: 0;
}

.form-actions {
  display: flex;
  gap: var(--space-3, 12px);
  margin-top: var(--space-5, 20px); /* reduziert von space-6 für dichteres Layout */
  align-items: center;
  flex-wrap: wrap;
}

.form-actions--right {
  justify-content: flex-end;
}

.form-actions--center {
  justify-content: center;
}

/* === Checkbox und Radio === */
.form-field--checkbox,
.form-field--radio {
  display: flex;
  align-items: center;
  gap: var(--space-3, 12px);
  margin-bottom: var(--space-4, 16px);
}

.form-field--checkbox input[type="checkbox"],
.form-field--radio input[type="radio"] {
  width: auto;
  margin: 0;
  cursor: pointer;
}

.form-field--checkbox label,
.form-field--radio label {
  margin: 0;
  font-weight: 400;
  cursor: pointer;
}

/* === Mobile Responsive === */
@media (max-width: 599px) {
  .form-field :is(input:not([type="checkbox"]):not([type="radio"]), select, textarea) {
    padding: var(--space-3, 12px);
    font-size: 16px; /* Prevents zoom on iOS */
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .form-actions {
    flex-direction: column;
    align-items: stretch;
  }
}

/* ====== PART 2: CORPUS-SPECIFIC LAYOUTS (Legacy) ====== */

/* Form Container */
.md3-corpus-form {
  display: grid;
  gap: var(--space-6);
  padding: var(--space-6);
  background: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-8);
}

/* Search Row (Query + Mode Select) */
.md3-corpus-search-row {
  display: flex;
  gap: var(--space-3);
  align-items: start;
  margin-bottom: var(--space-6);
  flex-wrap: wrap;
}

/* Desktop: Search + Mode nebeneinander */
.md3-corpus-search-row .md3-outlined-textfield {
  flex: 0 0 auto;
  min-width: 120px;
}

.md3-corpus-search-row .md3-outlined-textfield--flex {
  flex: 1 1 auto;
  min-width: 200px;
}

/* Modo/Search-Mode Select - Optimiert */
#search_mode {
  appearance: none;
}

/* Filter Grid (5 columns on desktop) */
.md3-corpus-filter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-3);
  align-items: start;
}

/* Regional filter section (below grid) */
.md3-regional-filter-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

/* Regional select field - match grid column width */
.md3-regional-select {
  margin-top: var(--space-1);
  width: 200px;
  min-width: 200px;
}

/* Ensure Select2 inside regional filter takes full width */
.md3-regional-select .select2-container {
  width: 200px !important;
}

/* ============================================================================
  Material Design 3 Checkbox (Custom Implementation)

  STATUS: ⚠️ Custom implementation, NOT canonical MD3
  @deprecated: this custom checkbox is a legacy implementation. It is
  kept to preserve current UI behavior, but the long-term plan is to
  replace it with a canonical `.md3-checkbox` implementation that
  matches the MD3 spec (focus ring, correct ripple behaviour, aria states).
  TODO: Provide a canonical `.md3-checkbox` implementation in a later
  change and migrate templates to `.md3-checkbox-legacy` when necessary.
  ============================================================================ */

.md3-checkbox-container {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  user-select: none;
  padding: 8px 0;
  position: relative;
}

.md3-checkbox-container input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
  margin: 0;
}

.md3-checkbox {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 18px;
  height: 18px;
  border: 2px solid var(--md-sys-color-outline-variant);
  border-radius: 2px;
  background-color: transparent;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  flex-shrink: 0;
}

/* Hover state */
.md3-checkbox-container:hover .md3-checkbox {
  border-color: var(--md-sys-color-on-surface);
}

/* Checked state */
.md3-checkbox-container input[type="checkbox"]:checked + .md3-checkbox {
  background-color: var(--md-sys-color-primary);
  border-color: var(--md-sys-color-primary);
}

/* Checkmark */
.md3-checkbox__checkmark {
  width: 12px;
  height: 12px;
  opacity: 0;
  transition: opacity 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

.md3-checkbox-container
  input[type="checkbox"]:checked
  + .md3-checkbox
  .md3-checkbox__checkmark {
  opacity: 1;
}

.md3-checkbox__checkmark-path {
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-dasharray: 22;
  stroke-dashoffset: 22;
  transition: stroke-dashoffset 0.2s cubic-bezier(0.4, 0, 0.2, 1) 0.1s;
}

.md3-checkbox-container
  input[type="checkbox"]:checked
  + .md3-checkbox
  .md3-checkbox__checkmark-path {
  stroke-dashoffset: 0;
}

/* Focus state */
.md3-checkbox-container input[type="checkbox"]:focus + .md3-checkbox {
  outline: 2px solid var(--md-sys-color-primary);
  outline-offset: 2px;
}

/* Label */
.md3-checkbox__label {
  /* font-family inherited from typography.css */
  font-size: 14px;
  line-height: 1.4;
  /* Use on-surface for better readability (not on-surface-variant) */
  color: var(--md-sys-color-on-surface);
  cursor: pointer;
}

/* Disabled state */
.md3-checkbox-container input[type="checkbox"]:disabled + .md3-checkbox {
  border-color: var(--md-sys-color-outline-variant);
  opacity: 0.38;
}

.md3-checkbox-container input[type="checkbox"]:disabled ~ .md3-checkbox__label {
  color: var(--md-sys-color-on-surface);
  opacity: 0.38;
}

/* Ripple effect (optional, simple version) */
.md3-checkbox::before {
  content: "";
  position: absolute;
  inset: -10px;
  border-radius: 50%;
  background-color: currentColor;
  opacity: 0;
  transition: opacity 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  pointer-events: none;
}

.md3-checkbox-container:active .md3-checkbox::before {
  opacity: 0.12;
}

/* Region field transition */
.md3-region-field {
  transition:
    opacity 0.2s cubic-bezier(0.4, 0, 0.2, 1),
    max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

/* Actions Row (Buttons Container) */
.md3-corpus-actions {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

/* ============================================================================
   Responsive Overrides (from corpus responsive section)
   ============================================================================ */

/* MD3 Compact (0-599px) */
@media (max-width: 599px) {
  .md3-corpus-search-row .md3-outlined-textfield {
    flex: 1 1 100%;
    min-width: 0;
    max-width: 100%;
  }

  #search_mode {
    font-size: 12px;
    padding: var(--space-2) var(--space-3);
    min-height: 40px;
  }

  #search_mode::after {
    display: none;
  }
}

@media (max-width: 400px) {
  #search_mode {
    font-size: 0.875rem;
    padding: var(--space-1) var(--space-2);
    min-height: 36px;
  }
}

/* TABLET: 601px - 1120px (accounting for 280px drawer) */
@media (max-width: 1120px) {
  .md3-corpus-form {
    gap: var(--space-5);
    padding: var(--space-5);
  }

  .md3-corpus-search-row {
    gap: var(--space-2);
    margin-bottom: var(--space-5);
  }

  .md3-corpus-filter-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-2);
  }
}

/* MOBILE STANDARD: MD3 Compact (0-599px) */
@media (max-width: 599px) {
  .md3-corpus-form {
    gap: var(--space-5);
    padding: var(--space-4) var(--space-3);
    margin-bottom: var(--space-6);
  }

  .md3-corpus-search-row {
    flex-direction: column;
    gap: var(--space-3);
    margin-bottom: var(--space-5);
  }

  /* Suchfeld volle Breite */
  .md3-corpus-search-row .md3-outlined-textfield--flex {
    flex: 1 1 100%;
    min-width: 0;
  }

  /* Mode-Select auch volle Breite */
  .md3-corpus-search-row .md3-outlined-textfield {
    flex: 1 1 100%;
    min-width: 0;
  }

  .md3-corpus-filter-grid {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }

  .md3-regional-select {
    width: 100%;
    min-width: auto;
  }

  .md3-regional-select .select2-container {
    width: 100% !important;
  }
}

/* MOBILE SMALL: ≤ 400px */
@media (max-width: 400px) {
  .md3-corpus-form {
    gap: var(--space-4);
    padding: var(--space-3) var(--space-2);
    margin-bottom: var(--space-4);
  }
}