/**
 * INVOICE FORM DESIGN SYSTEM STYLES
 * Zusätzliche CSS-Utilities und Variablen für das verbesserte Invoice-Formular
 *
 * Hinweis: Diese Styles sollten in das bestehende Tailwind CSS System integriert werden
 */

/* ========================================
   CSS Custom Properties (Design Tokens)
   ======================================== */

:root {
  /* Spacing System */
  --space-section-gap: 2rem;        /* 32px - Abstand zwischen Sektionen */
  --space-section-padding: 1.5rem;  /* 24px - Innen-Padding der Sektionen */
  --space-field-gap: 1rem;          /* 16px - Abstand zwischen Feldern */
  --space-inline-gap: 0.75rem;      /* 12px - Abstand zwischen Inline-Feldern */

  /* Component Heights */
  --height-form-element: 2.75rem;   /* 44px - Touch-friendly height */
  --height-button: 2.5rem;          /* 40px - Standard button height */
  --height-button-small: 2rem;      /* 32px - Small button height */

  /* Typography */
  --font-size-dialog-title: 1.5rem;    /* 24px */
  --font-size-section-title: 1.25rem;  /* 20px */
  --font-size-subsection: 1rem;        /* 16px */
  --font-size-body: 0.875rem;          /* 14px */
  --font-size-small: 0.75rem;          /* 12px */
  --font-size-large: 1rem;             /* 16px */

  /* Font Weights */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Border Radius */
  --radius-section: 0.75rem;    /* 12px */
  --radius-card: 0.5rem;        /* 8px */
  --radius-small: 0.375rem;     /* 6px */
  --radius-button: 0.375rem;    /* 6px */

  /* Shadows */
  --shadow-section: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-elevated: 0 4px 12px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.2s ease;
  --transition-slow: 0.3s ease;

  /* Z-Index Scale */
  --z-base: 1;
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* Dark Mode Adjustments */
.app-dark {
  --shadow-section: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-elevated: 0 4px 12px rgba(0, 0, 0, 0.35);
}

/* ========================================
   Form Section Components
   ======================================== */

.form-section {
  background: var(--surface-0);
  border: 1px solid var(--surface-200);
  border-radius: var(--radius-section);
  padding: var(--space-section-padding);
  box-shadow: var(--shadow-section);
  transition: box-shadow var(--transition-normal);
}

.form-section:hover {
  box-shadow: var(--shadow-hover);
}

.form-section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--surface-200);
}

.form-section-title {
  font-size: var(--font-size-section-title);
  font-weight: var(--font-weight-semibold);
  color: var(--text-primary);
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.form-section-body {
  /* Container for form fields */
}

/* ========================================
   Form Layout Utilities
   ======================================== */

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-field-gap);
  align-items: start;
}

.form-grid--3-col {
  grid-template-columns: repeat(3, 1fr);
}

.form-grid--4-col {
  grid-template-columns: repeat(4, 1fr);
}

.form-field-full {
  grid-column: 1 / -1;
}

.form-field-span-2 {
  grid-column: span 2;
}

/* Responsive Grid */
@media (max-width: 992px) {
  .form-grid,
  .form-grid--3-col,
  .form-grid--4-col {
    grid-template-columns: 1fr;
  }

  .form-field-span-2 {
    grid-column: span 1;
  }
}

/* ========================================
   Invoice Item Components
   ======================================== */

.invoice-items-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.invoice-item-card {
  background: var(--surface-50);
  border: 1px solid var(--surface-200);
  border-radius: var(--radius-card);
  padding: 1rem;
  transition: all var(--transition-normal);
}

.invoice-item-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--primary-color);
}

.invoice-item-card--new {
  animation: slideIn var(--transition-slow) ease-out;
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.invoice-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.invoice-item-number {
  font-weight: var(--font-weight-semibold);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.invoice-item-fields {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 1rem;
  align-items: start;
}

.invoice-item-field--small {
  max-width: 120px;
}

@media (max-width: 768px) {
  .invoice-item-fields {
    grid-template-columns: 1fr;
  }

  .invoice-item-field--small {
    max-width: 100%;
  }
}

.invoice-item-subtotal {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--surface-200);
}

/* ========================================
   Invoice Summary Component
   ======================================== */

.invoice-summary {
  background: linear-gradient(135deg, var(--primary-50) 0%, var(--primary-100) 100%);
  border: 2px solid var(--primary-color);
  border-radius: var(--radius-section);
  padding: 1.5rem;
  margin-top: 1.5rem;
}

.app-dark .invoice-summary {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.15) 0%, rgba(59, 130, 246, 0.25) 100%);
}

.invoice-summary-header {
  margin-bottom: 1rem;
}

.invoice-summary-header h4 {
  margin: 0;
  font-size: 1rem;
  font-weight: var(--font-weight-semibold);
  color: var(--text-primary);
}

.invoice-summary-body {
  /* Container for summary rows */
}

.invoice-summary-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.5rem 0;
  font-size: var(--font-size-body);
  color: var(--text-secondary);
}

.invoice-summary-total {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0 0;
  margin-top: 0.75rem;
  border-top: 2px solid var(--surface-200);
  font-size: 1.25rem;
  font-weight: var(--font-weight-bold);
  color: var(--text-primary);
}

/* ========================================
   Empty State Component
   ======================================== */

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 3rem 1rem;
  text-align: center;
}

.empty-state-icon {
  font-size: 3rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  opacity: 0.5;
}

.empty-state-text {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  font-weight: var(--font-weight-medium);
}

.empty-state-description {
  font-size: var(--font-size-small);
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

/* ========================================
   Form Actions
   ======================================== */

.form-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--surface-200);
  margin-top: 1.5rem;
}

.form-actions-secondary {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

@media (max-width: 768px) {
  .form-actions {
    flex-direction: column-reverse;
    align-items: stretch;
  }

  .form-actions-secondary {
    flex-direction: column;
    width: 100%;
  }
}

/* ========================================
   Context Card (Payment Form)
   ======================================== */

.context-card {
  background: linear-gradient(135deg, var(--primary-50) 0%, var(--primary-100) 100%);
  border: 1px solid var(--primary-200);
  border-radius: var(--radius-section);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.app-dark .context-card {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0.2) 100%);
  border-color: rgba(59, 130, 246, 0.3);
}

.context-card-header {
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--primary-200);
}

.context-card-header h4 {
  margin: 0;
  font-size: 1rem;
  font-weight: var(--font-weight-semibold);
}

.context-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.5rem 0;
}

.context-row--highlight {
  padding: 1rem 0 0;
  margin-top: 0.5rem;
  border-top: 1px solid var(--primary-300);
}

.context-label {
  color: var(--text-secondary);
  font-size: var(--font-size-body);
}

.context-value {
  text-align: right;
  font-weight: var(--font-weight-medium);
}

/* ========================================
   Upload Area (PDF Upload)
   ======================================== */

.upload-area {
  border: 2px dashed var(--surface-200);
  border-radius: var(--radius-section);
  padding: 3rem 2rem;
  text-align: center;
  transition: all var(--transition-normal);
  cursor: pointer;
  background: var(--surface-0);
}

.upload-area:hover {
  border-color: var(--primary-color);
  background: var(--primary-50);
}

.upload-area--dragover {
  border-color: var(--primary-color);
  background: var(--primary-100);
  border-width: 3px;
  transform: scale(1.02);
}

.upload-placeholder {
  /* Container for upload placeholder content */
}

.upload-icon {
  font-size: 4rem;
  color: var(--primary-color);
  margin-bottom: 1rem;
  opacity: 0.8;
}

.upload-hint {
  font-size: var(--font-size-small);
  color: var(--text-muted);
  margin-top: 1rem;
}

.upload-preview {
  /* Container for file preview */
}

.file-info {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
  background: var(--surface-50);
  border: 1px solid var(--surface-200);
  border-radius: var(--radius-card);
}

.file-icon {
  font-size: 2.5rem;
  color: var(--danger-color);
  flex-shrink: 0;
}

.file-details {
  flex: 1;
  text-align: left;
  min-width: 0; /* Allow text truncation */
}

.file-name {
  font-weight: var(--font-weight-semibold);
  margin-bottom: 0.25rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-size {
  font-size: var(--font-size-body);
  color: var(--text-secondary);
}

/* ========================================
   Keyboard Hints
   ======================================== */

.keyboard-hints {
  text-align: center;
  padding: 1rem;
  border-top: 1px solid var(--surface-200);
  margin-top: 1rem;
}

kbd {
  background: var(--surface-100);
  border: 1px solid var(--surface-300);
  border-radius: 0.25rem;
  padding: 0.125rem 0.375rem;
  font-size: var(--font-size-small);
  font-family: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Consolas, 'Liberation Mono', monospace;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

@media (max-width: 768px) {
  .keyboard-hints {
    display: none;
  }
}

/* ========================================
   Validation & Error States
   ======================================== */

.p-error {
  color: var(--danger-color);
  font-size: var(--font-size-small);
  margin-top: 0.25rem;
  display: block;
  animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Required field indicator */
abbr[title] {
  text-decoration: none;
  color: var(--danger-color);
  font-weight: var(--font-weight-bold);
  margin-left: 0.125rem;
}

/* ========================================
   List Transitions
   ======================================== */

.list-enter-active,
.list-leave-active {
  transition: all 0.3s ease;
}

.list-enter-from {
  opacity: 0;
  transform: translateY(-20px);
}

.list-leave-to {
  opacity: 0;
  transform: translateX(20px);
}

.list-move {
  transition: transform 0.3s ease;
}

/* ========================================
   Accessibility Utilities
   ======================================== */

/* Screen reader only content */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Focus visible styles */
*:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
  border-radius: var(--radius-small);
}

/* Skip to main content link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-color);
  color: white;
  padding: 8px 16px;
  text-decoration: none;
  z-index: var(--z-tooltip);
  border-radius: 0 0 var(--radius-small) 0;
  font-weight: var(--font-weight-medium);
}

.skip-link:focus {
  top: 0;
}

/* ========================================
   Loading States
   ======================================== */

.skeleton-loader {
  background: linear-gradient(
    90deg,
    var(--surface-200) 25%,
    var(--surface-100) 50%,
    var(--surface-200) 75%
  );
  background-size: 200% 100%;
  animation: loading 1.5s ease-in-out infinite;
  border-radius: var(--radius-small);
}

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

/* ========================================
   Utility Classes
   ======================================== */

/* Text utilities */
.text-muted {
  color: var(--text-muted);
}

.text-secondary {
  color: var(--text-secondary);
}

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

/* Spacing utilities */
.gap-section {
  gap: var(--space-section-gap);
}

.gap-field {
  gap: var(--space-field-gap);
}

.gap-inline {
  gap: var(--space-inline-gap);
}

/* Flex utilities */
.flex-between {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.flex-center {
  display: flex;
  justify-content: center;
  align-items: center;
}

/* ========================================
   Print Styles
   ======================================== */

@media print {
  .form-actions,
  .keyboard-hints,
  .invoice-item-actions,
  .form-section-header button {
    display: none !important;
  }

  .form-section {
    box-shadow: none;
    border: 1px solid #ddd;
    page-break-inside: avoid;
  }

  .invoice-summary {
    border: 2px solid #333;
    page-break-inside: avoid;
  }
}

/* ========================================
   Dark Mode Specific Adjustments
   ======================================== */

.app-dark .invoice-item-card {
  background: rgba(255, 255, 255, 0.05);
}

.app-dark .form-section {
  border-color: rgba(255, 255, 255, 0.1);
}

.app-dark kbd {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
}

/* ========================================
   High Contrast Mode Support
   ======================================== */

@media (prefers-contrast: high) {
  .form-section {
    border-width: 2px;
  }

  .invoice-item-card {
    border-width: 2px;
  }

  *:focus-visible {
    outline-width: 3px;
  }
}

/* ========================================
   Reduced Motion Support
   ======================================== */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}