/* ============================================
   REBURSE - Reimbursement Claim Form Styles
   Mobile-first responsive design
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-primary-light: #dbeafe;
  --color-success: #16a34a;
  --color-success-light: #dcfce7;
  --color-error: #dc2626;
  --color-error-light: #fee2e2;
  --color-warning: #f59e0b;
  --color-bg: #f1f5f9;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-border-focus: #93bbfd;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-text-light: #94a3b8;

  --color-mileage: #2563eb;
  --color-tolls: #16a34a;
  --color-food: #f59e0b;
  --color-transport: #7c3aed;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;

  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --max-width: 720px;
  --border-radius: 8px;
  --border-radius-sm: 4px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --transition: 150ms ease;
}

/* --- Reset & Base --- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* --- Header --- */
header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-xl) 0;
  text-align: center;
}

header h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-xs);
}

header .subtitle {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* --- Main --- */
main {
  flex: 1;
  padding: var(--space-xl) 0 var(--space-2xl);
  position: relative;
}

/* --- Fieldsets --- */
fieldset {
  border: none;
  background: var(--color-surface);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
}

legend {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text);
  padding-bottom: var(--space-md);
  margin-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
  width: 100%;
  display: block;
}

/* --- Form Groups --- */
.form-group {
  margin-bottom: var(--space-md);
}

.form-group label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-xs);
}

.required-marker {
  color: var(--color-error);
  font-weight: 600;
}

/* --- Inputs --- */
input[type="text"],
input[type="email"],
input[type="number"],
input[type="date"],
textarea,
select {
  width: 100%;
  min-height: 44px;
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-sm);
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
  -webkit-appearance: none;
}

select {
  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='%2364748b' d='M6 8.825L1.175 4 2.238 2.938 6 6.7 9.763 2.937 10.825 4z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

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

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

input[readonly] {
  background-color: var(--color-bg);
  color: var(--color-text-muted);
  cursor: default;
}

/* --- Validation Error State --- */
.form-group.has-error input,
.form-group.has-error textarea,
.form-group.has-error select {
  border-color: var(--color-error);
  box-shadow: 0 0 0 3px var(--color-error-light);
}

.field-error {
  display: none;
  font-size: 0.8125rem;
  color: var(--color-error);
  margin-top: var(--space-xs);
}

.form-group.has-error .field-error {
  display: block;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  font-weight: 600;
  border: none;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: background-color var(--transition), transform var(--transition);
  text-decoration: none;
}

.btn:active {
  transform: scale(0.98);
}

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

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

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

.btn-secondary {
  background-color: var(--color-bg);
  color: var(--color-primary);
  border: 1px solid var(--color-border);
}

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

.btn-danger {
  background-color: transparent;
  color: var(--color-error);
  padding: var(--space-xs) var(--space-sm);
  font-size: 0.8125rem;
  min-height: 32px;
}

.btn-danger:hover:not(:disabled) {
  background-color: var(--color-error-light);
}

/* --- Line Item Cards --- */
.line-item-card {
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-text-light);
  border-radius: var(--border-radius);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
  background: var(--color-surface);
  transition: border-left-color var(--transition);
}

.line-item-card[data-category="mileage"] {
  border-left-color: var(--color-mileage);
}

.line-item-card[data-category="tolls_parking"] {
  border-left-color: var(--color-tolls);
}

.line-item-card[data-category="food_meals"] {
  border-left-color: var(--color-food);
}

.line-item-card[data-category="transportation"] {
  border-left-color: var(--color-transport);
}

.line-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-md);
}

.line-item-number {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.dynamic-fields {
  margin-top: var(--space-md);
}

.field-row {
  display: grid;
  gap: var(--space-md);
  grid-template-columns: 1fr;
}

/* --- Notes Section --- */
.notes-section {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

.notes-section textarea {
  font-size: 0.875rem;
}

/* --- Receipt Upload --- */
.receipt-section {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
}

.receipt-section label {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

input[type="file"] {
  display: block;
  width: 100%;
  min-height: 44px;
  padding: var(--space-sm);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  border: 1px dashed var(--color-border);
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  background: var(--color-bg);
}

input[type="file"]:focus {
  outline: none;
  border-color: var(--color-primary);
}

.receipt-preview {
  display: none;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
  padding: var(--space-sm);
  background: var(--color-bg);
  border-radius: var(--border-radius-sm);
}

.receipt-preview.visible {
  display: flex;
}

.receipt-preview img {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--color-border);
}

.receipt-preview .file-icon {
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary-light);
  border-radius: var(--border-radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary);
}

.receipt-preview .receipt-name {
  flex: 1;
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* --- Add Item Button --- */
#add-item-btn {
  width: 100%;
  margin-bottom: var(--space-lg);
}

/* --- Expense Summary --- */
#expense-summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-md);
  background: var(--color-bg);
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--color-border);
}

.summary-label {
  font-weight: 600;
  font-size: 0.9375rem;
}

#running-total {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
}

/* --- Form Actions --- */
.form-actions {
  text-align: center;
  padding: var(--space-md) 0;
}

#submit-btn {
  width: 100%;
  max-width: 320px;
  font-size: 1rem;
  min-height: 48px;
}

/* --- Loading Overlay --- */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.overlay-content {
  background: var(--color-surface);
  padding: var(--space-xl) var(--space-2xl);
  border-radius: var(--border-radius);
  text-align: center;
  box-shadow: var(--shadow-lg);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto var(--space-md);
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* --- Feedback Cards --- */
.feedback-card {
  background: var(--color-surface);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  padding: var(--space-2xl);
  text-align: center;
  max-width: 480px;
  margin: var(--space-2xl) auto;
}

.feedback-icon {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 auto var(--space-md);
}

.feedback-success .feedback-icon {
  background: var(--color-success-light);
  color: var(--color-success);
}

.feedback-error .feedback-icon {
  background: var(--color-error-light);
  color: var(--color-error);
}

.feedback-card h2 {
  font-size: 1.25rem;
  margin-bottom: var(--space-sm);
}

.feedback-card p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-sm);
}

.submission-id {
  font-size: 0.875rem;
  color: var(--color-text);
  background: var(--color-bg);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--border-radius-sm);
  display: inline-block;
  margin: var(--space-sm) 0;
  word-break: break-all;
}

.feedback-note {
  font-size: 0.8125rem;
  font-style: italic;
}

.feedback-card .btn {
  margin-top: var(--space-lg);
}

/* --- Hidden Utility --- */
.hidden {
  display: none !important;
}

/* --- Footer --- */
footer {
  text-align: center;
  padding: var(--space-lg) 0;
  color: var(--color-text-light);
  font-size: 0.8125rem;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

/* --- Responsive: Tablet and up --- */
@media (min-width: 640px) {
  header h1 {
    font-size: 1.75rem;
  }

  fieldset {
    padding: var(--space-xl);
  }

  .field-row.two-col {
    grid-template-columns: 1fr 1fr;
  }

  .field-row.three-col {
    grid-template-columns: 1fr 1fr 1fr;
  }

  #add-item-btn {
    width: auto;
  }

  #submit-btn {
    width: auto;
    min-width: 240px;
  }
}