/**
 * ReportGen AI — UX System
 * Principles: Fitts's Law (44px targets), Proximity, Visual Hierarchy,
 * Material Design 3 + Apple HIG patterns, WCAG 2.2 accessibility
 */

:root {
  /* Spacing scale (8px base) */
  --ux-space-1: 0.25rem;
  --ux-space-2: 0.5rem;
  --ux-space-3: 0.75rem;
  --ux-space-4: 1rem;
  --ux-space-5: 1.25rem;
  --ux-space-6: 1.5rem;
  --ux-space-8: 2rem;

  /* Type scale */
  --ux-text-xs: 0.75rem;
  --ux-text-sm: 0.875rem;
  --ux-text-base: 1rem;
  --ux-text-lg: 1.125rem;
  --ux-text-xl: 1.25rem;
  --ux-text-2xl: 1.5rem;

  /* Radius (MD3) */
  --ux-radius-sm: 8px;
  --ux-radius-md: 12px;
  --ux-radius-lg: 16px;
  --ux-radius-full: 9999px;

  /* Touch targets (Fitts's Law / Apple HIG) */
  --ux-touch-min: 44px;

  /* Semantic feedback */
  --ux-info-bg: rgba(37, 99, 235, 0.1);
  --ux-info-border: rgba(37, 99, 235, 0.35);
  --ux-info-text: #1d4ed8;
  --ux-success-bg: rgba(5, 150, 105, 0.12);
  --ux-success-border: rgba(5, 150, 105, 0.35);
  --ux-success-text: #047857;
  --ux-warning-bg: rgba(245, 158, 11, 0.12);
  --ux-warning-border: rgba(245, 158, 11, 0.4);
  --ux-warning-text: #b45309;
  --ux-error-bg: rgba(220, 38, 38, 0.1);
  --ux-error-border: rgba(220, 38, 38, 0.35);
  --ux-error-text: #b91c1c;

  --ux-focus-ring: 0 0 0 3px rgba(37, 99, 235, 0.45);
  --ux-z-toast: 10000;
  --ux-z-confirm: 10050;
  --ux-z-skip: 10060;
}

/* Skip link (WCAG 2.4.1) */
.ux-skip-link {
  position: fixed;
  top: var(--ux-space-2);
  left: var(--ux-space-2);
  z-index: var(--ux-z-skip);
  padding: var(--ux-space-3) var(--ux-space-4);
  background: var(--bright-primary, #2563eb);
  color: #fff;
  font-weight: 600;
  font-size: var(--ux-text-sm);
  border-radius: var(--ux-radius-sm);
  text-decoration: none;
  transform: translateY(-200%);
  transition: transform 0.2s ease;
}
.ux-skip-link:focus {
  transform: translateY(0);
  outline: none;
  box-shadow: var(--ux-focus-ring);
}

/* Global focus (Recognition over recall) */
:focus-visible {
  outline: 2px solid var(--bright-primary, #2563eb);
  outline-offset: 2px;
}
button:focus:not(:focus-visible),
a:focus:not(:focus-visible) {
  outline: none;
}

/* Touch targets — marketing & shared */
.btn,
.nav-toggle,
.modal-close-btn,
.modal-close,
.launch-banner-close,
.auth-tab,
.demo-modal-step {
  min-height: var(--ux-touch-min);
}
.modal-close-btn,
.modal-close,
.launch-banner-close {
  min-width: var(--ux-touch-min);
  display: inline-grid;
  place-items: center;
}
.mobile-bottom-nav a {
  min-height: var(--ux-touch-min);
  padding-top: var(--ux-space-2);
  padding-bottom: calc(var(--ux-space-2) + env(safe-area-inset-bottom, 0px));
}

/* Form groups — Law of Proximity */
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--ux-space-2);
  margin-bottom: var(--ux-space-5);
}
.form-group label {
  font-size: var(--ux-text-sm);
  font-weight: 600;
  color: inherit;
}
.form-input,
.form-textarea,
.form-select {
  min-height: var(--ux-touch-min);
  padding: var(--ux-space-3) var(--ux-space-4);
  font-size: var(--ux-text-base);
  border-radius: var(--ux-radius-sm);
  transition: border-color 0.15s, box-shadow 0.15s;
}
.form-input.ux-invalid,
.form-textarea.ux-invalid {
  border-color: var(--ux-error-text) !important;
  box-shadow: 0 0 0 1px var(--ux-error-border);
}
.field-error {
  font-size: var(--ux-text-xs);
  color: var(--ux-error-text);
  display: flex;
  align-items: flex-start;
  gap: var(--ux-space-2);
  line-height: 1.4;
}
.field-error.hidden { display: none !important; }
.field-error::before {
  content: '⚠';
  flex-shrink: 0;
  font-size: 0.875rem;
}

/* Inline alerts (Nielsen: Error recovery) */
.alert,
.ux-alert {
  display: flex;
  align-items: flex-start;
  gap: var(--ux-space-3);
  padding: var(--ux-space-4);
  border-radius: var(--ux-radius-md);
  font-size: var(--ux-text-sm);
  line-height: 1.5;
  border: 1px solid transparent;
  margin-bottom: var(--ux-space-4);
}
.ux-alert__icon { flex-shrink: 0; font-size: 1.125rem; line-height: 1.3; }
.ux-alert__body { flex: 1; min-width: 0; }
.ux-alert__dismiss {
  flex-shrink: 0;
  min-width: 36px;
  min-height: 36px;
  border: none;
  background: transparent;
  cursor: pointer;
  border-radius: var(--ux-radius-sm);
  opacity: 0.7;
  font-size: 1.25rem;
  line-height: 1;
}
.ux-alert__dismiss:hover { opacity: 1; }

.alert-info, .ux-alert--info {
  background: var(--ux-info-bg);
  border-color: var(--ux-info-border);
  color: var(--ux-info-text);
}
.alert-success, .ux-alert--success {
  background: var(--ux-success-bg);
  border-color: var(--ux-success-border);
  color: var(--ux-success-text);
}
.alert-warning, .ux-alert--warning {
  background: var(--ux-warning-bg);
  border-color: var(--ux-warning-border);
  color: var(--ux-warning-text);
}
.alert-error, .ux-alert--error {
  background: var(--ux-error-bg);
  border-color: var(--ux-error-border);
  color: var(--ux-error-text);
}

/* Dark app context */
.app-body .alert-info, .app-body .ux-alert--info { color: #a5b4fc; background: rgba(99, 102, 241, 0.12); border-color: rgba(99, 102, 241, 0.3); }
.app-body .alert-success, .app-body .ux-alert--success { color: #6ee7b7; }
.app-body .alert-error, .app-body .ux-alert--error { color: #fca5a5; }

/* Toast stack (aria-live region) */
.ux-toast-region {
  position: fixed;
  bottom: calc(1rem + env(safe-area-inset-bottom, 0px));
  right: 1rem;
  left: auto;
  z-index: var(--ux-z-toast);
  display: flex;
  flex-direction: column-reverse;
  gap: var(--ux-space-3);
  max-width: min(420px, calc(100vw - 2rem));
  pointer-events: none;
}
body.has-mobile-nav .ux-toast-region {
  bottom: calc(4.5rem + env(safe-area-inset-bottom, 0px));
}
body.app-body .ux-toast-region {
  bottom: calc(1.5rem + env(safe-area-inset-bottom, 0px));
}

.ux-toast {
  pointer-events: auto;
  display: flex;
  align-items: flex-start;
  gap: var(--ux-space-3);
  padding: var(--ux-space-4) var(--ux-space-5);
  border-radius: var(--ux-radius-md);
  font-size: var(--ux-text-sm);
  font-weight: 500;
  line-height: 1.45;
  color: #fff;
  box-shadow: 0 8px 32px rgba(15, 23, 42, 0.2);
  animation: ux-toast-in 0.28s cubic-bezier(0.2, 0.9, 0.3, 1);
  border: 1px solid rgba(255, 255, 255, 0.12);
}
.ux-toast--info { background: #2563eb; }
.ux-toast--success { background: #059669; }
.ux-toast--warning { background: #d97706; }
.ux-toast--error { background: #dc2626; }
.ux-toast__icon { flex-shrink: 0; }
.ux-toast__msg { flex: 1; }
.ux-toast__close {
  flex-shrink: 0;
  min-width: 32px;
  min-height: 32px;
  border: none;
  background: rgba(255, 255, 255, 0.15);
  color: inherit;
  border-radius: var(--ux-radius-sm);
  cursor: pointer;
  font-size: 1.125rem;
  line-height: 1;
}
.ux-toast__close:hover { background: rgba(255, 255, 255, 0.25); }
.ux-toast.ux-toast--out { animation: ux-toast-out 0.2s ease forwards; }

@keyframes ux-toast-in {
  from { opacity: 0; transform: translateY(12px) scale(0.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
@keyframes ux-toast-out {
  to { opacity: 0; transform: translateY(8px); }
}

/* Confirm dialog */
.ux-confirm-backdrop {
  position: fixed;
  inset: 0;
  z-index: var(--ux-z-confirm);
  background: rgba(15, 23, 42, 0.55);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--ux-space-6);
  animation: ux-fade-in 0.2s ease;
}
.ux-confirm {
  width: 100%;
  max-width: 400px;
  background: var(--bright-surface, #fff);
  border-radius: var(--ux-radius-lg);
  padding: var(--ux-space-6);
  box-shadow: 0 24px 64px rgba(15, 23, 42, 0.2);
  border: 1px solid var(--bright-border, #cbd5e1);
}
.app-body .ux-confirm {
  background: #141820;
  border-color: rgba(255, 255, 255, 0.1);
  color: #f1f5f9;
}
.ux-confirm h2 {
  margin: 0 0 var(--ux-space-3);
  font-size: var(--ux-text-lg);
}
.ux-confirm p {
  margin: 0 0 var(--ux-space-6);
  font-size: var(--ux-text-sm);
  color: var(--bright-muted, #475569);
  line-height: 1.55;
}
.app-body .ux-confirm p { color: #94a3b8; }
.ux-confirm__actions {
  display: flex;
  gap: var(--ux-space-3);
  justify-content: flex-end;
  flex-wrap: wrap;
}

/* Modal a11y enhancements */
.enterprise-modal-backdrop[aria-hidden="true"],
.modal-backdrop[aria-hidden="true"] {
  display: none !important;
}
.enterprise-modal-backdrop.open,
.modal-backdrop.open {
  display: flex !important;
}

/* Visual hierarchy helpers */
.ux-section-label {
  font-size: var(--ux-text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--bright-primary, #2563eb);
  margin-bottom: var(--ux-space-2);
}
.ux-help-text {
  font-size: var(--ux-text-xs);
  color: var(--bright-muted, #64748b);
  margin-top: var(--ux-space-1);
  line-height: 1.45;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .ux-toast,
  .ux-confirm-backdrop,
  .ux-skip-link {
    animation: none !important;
    transition: none !important;
  }
}

@keyframes ux-fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Responsive — Hick's Law: simplify nav on small screens (handled in existing CSS) */
@media (max-width: 768px) {
  .ux-toast-region {
    left: 1rem;
    right: 1rem;
    max-width: none;
  }
}