/**
 * Main Stylesheet - Bewirtungsbeleg
 *
 * Classless-first approach with minimal utility classes.
 * Mobile-first, responsive design.
 *
 * @see ADR-004: Semantic HTML and CSS
 */

/* =============================================================================
   CSS CUSTOM PROPERTIES (DESIGN TOKENS)
   ============================================================================= */

:root {
  /* Colors */
  --color-text: #1a1a1a;
  --color-text-muted: #666;
  --color-background: #fff;
  --color-surface: #f8f9fa;
  --color-border: #dee2e6;
  --color-primary: #0066cc;
  --color-primary-hover: #0052a3;
  --color-error: #c62828;
  --color-error-bg: #ffebee;
  --color-warning: #e65100;
  --color-warning-bg: #fff3e0;
  --color-success: #2e7d32;
  --color-success-bg: #e8f5e9;

  /* Typography */
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-base: 16px;
  --font-size-sm: 0.875rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.5rem;
  --line-height: 1.5;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;

  /* Layout */
  --max-width: 1200px;
  --border-radius: 4px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* =============================================================================
   BASE / RESET
   ============================================================================= */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: var(--font-size-base);
  line-height: var(--line-height);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  color: var(--color-text);
  background-color: var(--color-background);
}

/* =============================================================================
   TYPOGRAPHY
   ============================================================================= */

h1, h2, h3, h4, h5, h6 {
  margin-top: 0;
  margin-bottom: var(--space-md);
  font-weight: 600;
  line-height: 1.25;
}

h1 {
  font-size: var(--font-size-xl);
}

h2 {
  font-size: var(--font-size-lg);
}

h3 {
  font-size: var(--font-size-base);
}

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

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

a:hover,
a:focus {
  text-decoration: underline;
}

/* =============================================================================
   LAYOUT
   ============================================================================= */

body > header {
  padding: var(--space-md) var(--space-lg);
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

body > header h1 {
  margin-bottom: var(--space-xs);
}

body > header .privacy-notice {
  margin: 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

main {
  padding: var(--space-lg);
  max-width: var(--max-width);
  margin: 0 auto;
}

.layout {
  display: grid;
  gap: var(--space-xl);
}

@media (min-width: 900px) {
  .layout {
    grid-template-columns: 1fr 400px;
  }
}

body > footer {
  padding: var(--space-lg);
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  border-top: 1px solid var(--color-border);
}

body > footer .version {
  margin-bottom: 0;
}

/* =============================================================================
   FORMS
   ============================================================================= */

fieldset {
  margin: 0 0 var(--space-lg) 0;
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  background-color: var(--color-surface);
}

legend {
  padding: 0 var(--space-sm);
  font-weight: 600;
  font-size: var(--font-size-base);
}

.field {
  margin-bottom: var(--space-md);
}

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

.field-row {
  display: grid;
  gap: var(--space-md);
}

@media (min-width: 600px) {
  .field-row {
    grid-template-columns: 1fr 1fr;
  }
}

label {
  display: block;
  margin-bottom: var(--space-xs);
  font-weight: 500;
  font-size: var(--font-size-sm);
}

input[type="text"],
input[type="number"],
input[type="date"],
input[type="email"],
input[type="tel"],
textarea,
select {
  display: block;
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  font-family: inherit;
  font-size: var(--font-size-base);
  line-height: var(--line-height);
  color: var(--color-text);
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  transition: border-color 0.15s, box-shadow 0.15s;
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.15);
}

input[aria-invalid="true"],
textarea[aria-invalid="true"],
select[aria-invalid="true"] {
  border-color: var(--color-error);
}

input[aria-invalid="true"]:focus,
textarea[aria-invalid="true"]:focus,
select[aria-invalid="true"]:focus {
  box-shadow: 0 0 0 3px rgba(198, 40, 40, 0.15);
}

textarea {
  resize: vertical;
  min-height: 80px;
}

select {
  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='%23666' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

.input-with-suffix {
  display: flex;
  align-items: stretch;
}

.input-with-suffix input {
  flex: 1;
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

.input-with-suffix .suffix {
  display: flex;
  align-items: center;
  padding: 0 var(--space-md);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: none;
  border-radius: 0 var(--border-radius) var(--border-radius) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.hint {
  margin: var(--space-xs) 0 0 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.error {
  margin: var(--space-xs) 0 0 0;
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-sm);
  color: var(--color-error);
  background-color: var(--color-error-bg);
  border-radius: var(--border-radius);
}

.warning {
  margin: var(--space-xs) 0 0 0;
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-sm);
  color: var(--color-warning);
  background-color: var(--color-warning-bg);
  border-radius: var(--border-radius);
}

.conditional-fields {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px dashed var(--color-border);
}

/* =============================================================================
   BUTTONS
   ============================================================================= */

button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-sm) var(--space-lg);
  font-family: inherit;
  font-size: var(--font-size-base);
  font-weight: 500;
  line-height: var(--line-height);
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
}

button:hover,
button:focus {
  background-color: var(--color-border);
}

button:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.15);
}

button.primary {
  color: #fff;
  background-color: var(--color-primary);
  border-color: var(--color-primary);
}

button.primary:hover,
button.primary:focus {
  background-color: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
}

.form-actions {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-top: var(--space-lg);
}

/* =============================================================================
   RECENT LOCATIONS
   ============================================================================= */

.recent-locations {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-top: var(--space-sm);
}

.recent-locations button {
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--font-size-sm);
}

/* =============================================================================
   PREVIEW SECTION
   ============================================================================= */

.preview-section {
  position: sticky;
  top: var(--space-lg);
}

.preview-section h2 {
  margin-bottom: var(--space-md);
}

.preview {
  padding: var(--space-md);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  min-height: 200px;
}

.preview-empty {
  color: var(--color-text-muted);
  font-style: italic;
  text-align: center;
  margin: var(--space-xl) 0;
}

.preview dl {
  margin: 0;
}

.preview dt {
  font-weight: 600;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-md);
}

.preview dt:first-child {
  margin-top: 0;
}

.preview dd {
  margin: var(--space-xs) 0 0 0;
}

/* Preview Receipt Image */
.preview-image-container {
  margin-bottom: var(--space-md);
}

.preview-image-container h3 {
  margin-bottom: var(--space-sm);
  font-size: var(--font-size-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
}

.preview-receipt-image {
  display: block;
  max-width: 100%;
  max-height: 200px;
  margin: 0 auto;
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  object-fit: contain;
  background-color: var(--color-surface);
}

/* =============================================================================
   CALCULATIONS
   ============================================================================= */

.calculations {
  margin-top: var(--space-lg);
}

.calculations h3 {
  margin-top: var(--space-md);
  margin-bottom: var(--space-sm);
  font-size: var(--font-size-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
}

.calculations h3:first-child {
  margin-top: 0;
}

.calculations table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--font-size-sm);
}

.calculations td {
  padding: var(--space-xs) 0;
}

.calculations td.amount {
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.calculations tr.total td {
  padding-top: var(--space-sm);
  font-weight: 600;
  border-top: 1px solid var(--color-border);
}

/* =============================================================================
   WARNINGS
   ============================================================================= */

.warnings {
  margin-top: var(--space-md);
  padding: var(--space-md);
  background-color: var(--color-warning-bg);
  border-radius: var(--border-radius);
}

.warnings p {
  margin: 0;
  font-size: var(--font-size-sm);
  color: var(--color-warning);
}

.warnings p + p {
  margin-top: var(--space-sm);
}

/* =============================================================================
   OCR SECTION
   ============================================================================= */

.ocr-section {
  margin-bottom: var(--space-lg);
}

.ocr-dropzone {
  position: relative;
  padding: var(--space-xl);
  text-align: center;
  border: 2px dashed var(--color-border);
  border-radius: var(--border-radius);
  background-color: var(--color-background);
  cursor: pointer;
  transition: border-color 0.15s, background-color 0.15s;
}

.ocr-dropzone:hover,
.ocr-dropzone.dragover {
  border-color: var(--color-primary);
  background-color: rgba(0, 102, 204, 0.05);
}

.dropzone-content {
  pointer-events: none;
}

.dropzone-icon {
  margin-bottom: var(--space-md);
  color: var(--color-text-muted);
}

.dropzone-text {
  margin: 0;
  font-weight: 500;
  color: var(--color-text);
}

.dropzone-hint {
  margin: var(--space-xs) 0 0 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.dropzone-formats {
  margin: var(--space-sm) 0 0 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.ocr-preview {
  position: relative;
  margin-top: var(--space-md);
  border-radius: var(--border-radius);
  overflow: hidden;
}

.ocr-preview img {
  display: block;
  max-width: 100%;
  max-height: 300px;
  margin: 0 auto;
  border-radius: var(--border-radius);
  border: 1px solid var(--color-border);
}

.ocr-remove-btn {
  position: absolute;
  top: var(--space-sm);
  right: var(--space-sm);
  width: 32px;
  height: 32px;
  padding: 0;
  font-size: 1.25rem;
  font-weight: bold;
  color: #fff;
  background-color: rgba(0, 0, 0, 0.6);
  border: none;
  border-radius: 50%;
  cursor: pointer;
}

.ocr-remove-btn:hover {
  background-color: var(--color-error);
}

.ocr-progress {
  margin-top: var(--space-md);
  text-align: center;
}

.progress-bar {
  height: 8px;
  background-color: var(--color-border);
  border-radius: 4px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0;
  background-color: var(--color-primary);
  border-radius: 4px;
  transition: width 0.2s ease-out;
}

.progress-status {
  margin: var(--space-sm) 0 0 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.ocr-result {
  margin-top: var(--space-md);
  padding: var(--space-md);
  text-align: center;
  background-color: var(--color-success-bg);
  border-radius: var(--border-radius);
}

.ocr-success {
  margin: 0 0 var(--space-md) 0;
  color: var(--color-success);
  font-weight: 500;
}

.ocr-error {
  margin-top: var(--space-md);
  padding: var(--space-md);
  text-align: center;
  background-color: var(--color-error-bg);
  border-radius: var(--border-radius);
}

.ocr-error .error-message {
  margin: 0 0 var(--space-md) 0;
  color: var(--color-error);
}

/* =============================================================================
   PRINT DOCUMENT (HIDDEN ON SCREEN)
   ============================================================================= */

.print-document {
  display: none;
}

/* =============================================================================
   UTILITY CLASSES
   ============================================================================= */

[hidden] {
  display: none !important;
}

/* =============================================================================
   ACCESSIBILITY
   ============================================================================= */

/* Skip to main content link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--space-sm) var(--space-md);
  z-index: 100;
  text-decoration: none;
}

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

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

/* Ensure focus is visible */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

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

/* =============================================================================
   OFFLINE INDICATOR
   ============================================================================= */

.offline-indicator {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-warning);
  color: white;
  text-align: center;
  font-size: var(--font-size-sm);
  font-weight: 500;
  z-index: 9999;
  transform: translateY(-100%);
  transition: transform 0.3s ease-out;
}

.offline-indicator.visible {
  transform: translateY(0);
}

.offline-indicator + header {
  margin-top: 40px;
}

/* Update notification for new version */
.update-notification {
  position: fixed;
  bottom: var(--space-lg);
  left: 50%;
  transform: translateX(-50%);
  padding: var(--space-md) var(--space-lg);
  background-color: var(--color-primary);
  color: white;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
  z-index: 9999;
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-size: var(--font-size-sm);
}

.update-notification button {
  padding: var(--space-xs) var(--space-md);
  background-color: white;
  color: var(--color-primary);
  border: none;
  border-radius: var(--border-radius);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
}

.update-notification button:hover {
  background-color: var(--color-surface);
}

/* =============================================================================
   BREADCRUMB NAVIGATION
   ============================================================================= */

.breadcrumb {
  margin-bottom: var(--space-lg);
}

.breadcrumb a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--font-size-sm);
  color: var(--color-primary);
}

.breadcrumb a::before {
  content: '\2190';
}

/* =============================================================================
   SCAN LINK SECTION
   ============================================================================= */

.scan-link-section {
  margin-bottom: var(--space-lg);
  padding: var(--space-md);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  text-align: center;
}

.scan-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  font-weight: 500;
  color: var(--color-primary);
  background-color: var(--color-background);
  border: 2px dashed var(--color-primary);
  border-radius: var(--border-radius);
  transition: background-color 0.15s, border-style 0.15s;
}

.scan-link:hover {
  background-color: rgba(0, 102, 204, 0.05);
  border-style: solid;
  text-decoration: none;
}

.scan-link svg {
  flex-shrink: 0;
}

.scan-link-section .hint {
  margin-top: var(--space-sm);
  margin-bottom: 0;
}

/* =============================================================================
   SCAN PAGE
   ============================================================================= */

.scan-page {
  max-width: 600px;
  margin: 0 auto;
}

.scan-info {
  margin-top: var(--space-xl);
  padding: var(--space-lg);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
}

.scan-info h2 {
  margin-top: 0;
}

.scan-info ol {
  margin: 0 0 var(--space-md) 0;
  padding-left: var(--space-lg);
}

.scan-info li {
  margin-bottom: var(--space-sm);
}

.scan-info .hint {
  margin-bottom: 0;
}

.ocr-extracted-data {
  margin: var(--space-md) 0;
  text-align: left;
}

.ocr-extracted-data dl {
  margin: 0;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-xs) var(--space-md);
}

.ocr-extracted-data dt {
  font-weight: 600;
  color: var(--color-text-muted);
}

.ocr-extracted-data dd {
  margin: 0;
}

/* =============================================================================
   IMPORT/EXPORT PAGE
   ============================================================================= */

.import-export-page {
  max-width: 800px;
  margin: 0 auto;
}

.ie-grid {
  display: grid;
  gap: var(--space-lg);
}

@media (min-width: 600px) {
  .ie-grid {
    grid-template-columns: 1fr 1fr;
  }

  .ie-grid .ie-section-danger {
    grid-column: 1 / -1;
  }
}

.ie-section {
  margin: 0;
}

.ie-section p {
  margin-bottom: var(--space-sm);
}

.ie-section p:last-of-type {
  margin-bottom: var(--space-md);
}

.ie-actions {
  display: flex;
  gap: var(--space-md);
}

.ie-actions button {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
}

.ie-actions button svg {
  flex-shrink: 0;
}

.ie-section-danger {
  border-color: var(--color-error);
  background-color: var(--color-error-bg);
}

.ie-section-danger legend {
  color: var(--color-error);
}

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

button.danger:hover,
button.danger:focus {
  background-color: #b71c1c;
  border-color: #b71c1c;
}

.warning-text {
  color: var(--color-error);
}

/* Statistics Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-md);
}

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

.stat-value {
  display: block;
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-primary);
}

.stat-label {
  display: block;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
}