/* ARD Auth Service — Design Tokens & Global Styles
   Mobile-first, WCAG 2.1 AA, no build step required
   ------------------------------------------------------------------ */

/* ── Design Tokens ─────────────────────────────────────────────────── */
:root {
  /* Brand colors */
  --color-primary: #1a73e8;
  --color-primary-hover: #1557b0;
  --color-danger: #d93025;
  --color-danger-hover: #b3261e;
  --color-success: #1e8e3e;
  --color-warning: #f9ab00;

  /* Social login provider colors (provider-mandated) */
  --color-google: #4285f4;
  --color-google-hover: #3367d6;
  --color-apple: #000000;
  --color-apple-hover: #1a1a1a;

  /* Text colors */
  --color-text: #202124;
  --color-text-secondary: #5f6368;
  --color-disabled-text: #80868b;

  /* Surface & border colors */
  --color-background: #ffffff;
  --color-surface: #f8f9fa;
  --color-border: #dadce0;
  --color-disabled: #dadce0;
  --color-error-bg: #fce8e6;

  /* Skeleton loading colors */
  --color-skeleton: #e8eaed;
  --color-skeleton-shimmer: #f1f3f4;

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-mono: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  --font-size-xs: 0.75rem;     /* 12px — legal text, timestamps */
  --font-size-sm: 0.875rem;    /* 14px — secondary text, subtitles */
  --font-size-base: 1rem;      /* 16px — body text, form labels */
  --font-size-lg: 1.25rem;     /* 20px — section headings */
  --font-size-xl: 1.5rem;      /* 24px — page title */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-bold: 600;

  /* Spacing */
  --space-xs: 0.25rem;   /* 4px */
  --space-sm: 0.5rem;    /* 8px */
  --space-md: 1rem;      /* 16px */
  --space-lg: 1.5rem;    /* 24px */
  --space-xl: 2rem;      /* 32px */
  --space-2xl: 3rem;     /* 48px */

  /* Layout */
  --max-width-form: 400px;
  --max-width-settings: 600px;
  --border-radius: 8px;
  --border-radius-sm: 4px;

  /* Shadows */
  --shadow-card: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.08);
  --shadow-modal: 0 4px 16px rgba(0,0,0,0.16);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;

  /* Accessibility */
  --focus-ring: 0 0 0 3px rgba(26, 115, 232, 0.4);
  --min-tap-target: 44px;
}

/* ── Reduced Motion ─────────────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none !important;
    animation: none !important;
  }
}

/* ── Skeleton shimmer animation ─────────────────────────────────────── */
@keyframes skeleton-shimmer {
  0%   { background-position: -200% 0; }
  100% { background-position:  200% 0; }
}

.skeleton {
  background: linear-gradient(
    90deg,
    var(--color-skeleton) 25%,
    var(--color-skeleton-shimmer) 50%,
    var(--color-skeleton) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: var(--border-radius-sm);
}

/* ── Global 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-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* ── Skip-to-content link ───────────────────────────────────────────── */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  z-index: 100;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-primary);
  color: #fff;
  border-radius: var(--border-radius-sm);
  font-weight: var(--font-weight-medium);
  text-decoration: none;
  transition: top var(--transition-fast);
}
.skip-link:focus {
  top: var(--space-md);
}

/* ── Focus rings on all interactive elements ────────────────────────── */
:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* ── Auth form layout ────────────────────────────────────────────────── */
.auth-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-lg);
  background-color: var(--color-background);
}

.auth-form {
  width: 100%;
  padding: var(--space-lg);
}

/* Desktop: centered card */
@media (min-width: 768px) {
  .auth-container {
    background-color: var(--color-surface);
    padding: var(--space-2xl) var(--space-lg);
  }

  .auth-form {
    max-width: var(--max-width-form);
    margin: 0 auto;
    background-color: var(--color-background);
    padding: var(--space-xl);
    box-shadow: var(--shadow-card);
    border-radius: var(--border-radius);
  }

  .settings-form {
    max-width: var(--max-width-settings);
  }
}

/* ── Typography helpers ──────────────────────────────────────────────── */
.page-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  margin-bottom: var(--space-lg);
}

.section-heading {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  margin-bottom: var(--space-md);
}

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

/* ── Buttons ─────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  min-height: var(--min-tap-target);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  border: none;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--transition-fast), box-shadow var(--transition-fast);
  width: 100%;
}

.btn:focus-visible {
  box-shadow: var(--focus-ring);
}

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

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

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

.btn:disabled,
.btn[aria-disabled="true"] {
  background-color: var(--color-disabled);
  color: var(--color-disabled-text);
  cursor: not-allowed;
}

/* Social buttons */
.btn-google {
  background-color: var(--color-google);
  color: #fff;
}
.btn-google:hover { background-color: var(--color-google-hover); }

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

/* ── Form fields ─────────────────────────────────────────────────────── */
.form-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.form-field label {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
}

.form-field input,
.form-field select,
.form-field textarea {
  width: 100%;
  min-height: var(--min-tap-target);
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-sm);
  transition: border-color var(--transition-fast);
}

.form-field input:focus-visible {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: var(--focus-ring);
}

.form-field input[aria-invalid="true"] {
  border-color: var(--color-danger);
}

.form-field-error {
  font-size: var(--font-size-sm);
  color: var(--color-danger);
  min-height: 1.25rem; /* reserve space to avoid layout shift */
}

/* ── Social divider ──────────────────────────────────────────────────── */
.social-divider {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin: var(--space-lg) 0;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}
.social-divider::before,
.social-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background-color: var(--color-border);
}

/* ── Error banner ────────────────────────────────────────────────────── */
.error-banner {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  padding: var(--space-md);
  background-color: var(--color-error-bg);
  border-left: 3px solid var(--color-danger);
  border-radius: var(--border-radius-sm);
  margin-bottom: var(--space-lg);
}

.error-banner-message {
  flex: 1;
  font-size: var(--font-size-sm);
  color: var(--color-danger);
}

.error-banner-action {
  font-size: var(--font-size-sm);
  color: var(--color-primary);
  text-decoration: underline;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  white-space: nowrap;
}

/* ── Agreement checkboxes ────────────────────────────────────────────── */
.agreement-item {
  display: flex;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-border);
}

.agreement-item:last-child { border-bottom: none; }

.agreement-icon {
  font-size: var(--font-size-lg);
  flex-shrink: 0;
  width: var(--min-tap-target);
  text-align: center;
}

.agreement-content { flex: 1; }

.agreement-title {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
}

.agreement-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  margin-top: var(--space-xs);
}

.agreement-checkbox-row {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
}

.agreement-checkbox-row input[type="checkbox"] {
  width: 20px;
  height: 20px;
  cursor: pointer;
  accent-color: var(--color-primary);
}

/* Optional agreement separator */
.agreement-optional-label {
  display: inline-block;
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
  background-color: var(--color-surface);
  padding: 2px var(--space-xs);
  border-radius: var(--border-radius-sm);
  margin-left: var(--space-xs);
}

/* ── Password strength indicator ─────────────────────────────────────── */
.password-strength {
  margin-top: var(--space-xs);
}

.password-strength-bar {
  height: 4px;
  border-radius: 2px;
  background-color: var(--color-border);
  overflow: hidden;
}

.password-strength-fill {
  height: 100%;
  border-radius: 2px;
  transition: width var(--transition-base), background-color var(--transition-base);
}

.password-strength-label {
  font-size: var(--font-size-xs);
  margin-top: var(--space-xs);
}

.strength-weak   { background-color: var(--color-danger); }
.strength-medium { background-color: var(--color-warning); }
.strength-strong { background-color: var(--color-success); }

/* ── Session list ────────────────────────────────────────────────────── */
.session-item {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-md) 0;
  border-bottom: 1px solid var(--color-border);
}

.session-item:last-child { border-bottom: none; }

.session-meta { flex: 1; }
.session-device { font-weight: var(--font-weight-medium); }
.session-detail { font-size: var(--font-size-sm); color: var(--color-text-secondary); }
.session-current {
  font-size: var(--font-size-xs);
  color: var(--color-success);
  font-weight: var(--font-weight-medium);
}

/* ── Re-auth Modal (.reauth-*) ───────────────────────────────────────── */
/* Full-page render styled as an overlay — visually resembles a modal.   */
.reauth-overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.48);
  padding: var(--space-lg);
}

.reauth-card {
  background: var(--color-background);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-modal);
  padding: var(--space-2xl) var(--space-xl);
  width: 100%;
  max-width: 360px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-lg);
  text-align: center;
}

.reauth-avatar {
  width: 64px;
  height: 64px;
  flex-shrink: 0;
}

.reauth-avatar-img {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  object-fit: cover;
}

.reauth-avatar-placeholder {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--color-primary);
  color: var(--color-background);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  display: flex;
  align-items: center;
  justify-content: center;
}

.reauth-heading {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  margin: 0;
}

.reauth-error {
  font-size: var(--font-size-sm);
  color: var(--color-danger);
  background: var(--color-error-bg);
  border-radius: var(--border-radius);
  padding: var(--space-sm) var(--space-md);
  width: 100%;
  margin: 0;
}

.reauth-social-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  text-decoration: none;
}

.reauth-form {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.reauth-submit {
  width: 100%;
}

.reauth-different-method {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  text-decoration: none;
}

.reauth-different-method:hover {
  color: var(--color-primary);
  text-decoration: underline;
}

/* ── Settings page ───────────────────────────────────────────────────── */
.settings-container {
  max-width: var(--max-width-settings);
  margin: 0 auto;
  padding: var(--space-lg) var(--space-md);
}

.settings-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.settings-avatar {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  flex-shrink: 0;
  object-fit: cover;
}

.settings-avatar-placeholder {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #fff;
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.settings-user-name {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
}

.settings-user-email {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

/* Accordion (mobile) */
.accordion-item {
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  margin-bottom: var(--space-sm);
  overflow: hidden;
}

.accordion-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  background: var(--color-background);
  border: none;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  cursor: pointer;
  text-align: left;
  min-height: var(--min-tap-target);
}

.accordion-trigger:focus-visible { box-shadow: var(--focus-ring); }

.accordion-trigger[aria-expanded="true"] .accordion-chevron {
  transform: rotate(180deg);
}

.accordion-chevron {
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.accordion-panel {
  padding: var(--space-lg);
  border-top: 1px solid var(--color-border);
  background: var(--color-background);
}

.accordion-panel[hidden] { display: none; }

/* Tabs (desktop, 768px+) */
@media (min-width: 768px) {
  .accordion-item { border: none; margin-bottom: 0; border-radius: 0; }
  .accordion-trigger { display: none; }
  .accordion-panel { display: block !important; padding: 0; border: none; }

  .settings-tabs {
    display: flex;
    border-bottom: 2px solid var(--color-border);
    margin-bottom: var(--space-xl);
    gap: 0;
  }

  .settings-tab {
    padding: var(--space-md) var(--space-lg);
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    cursor: pointer;
    white-space: nowrap;
  }

  .settings-tab:hover { color: var(--color-primary); }
  .settings-tab:focus-visible { box-shadow: var(--focus-ring); }

  .settings-tab[aria-selected="true"] {
    color: var(--color-primary);
    border-bottom-color: var(--color-primary);
  }

  .settings-panel { display: none; }
  .settings-panel.is-active { display: block; }
}

/* Settings section content */
.settings-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  padding: var(--space-md) 0;
}

.settings-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--color-border);
}

.settings-row:last-child { border-bottom: none; }

.settings-row-label { font-weight: var(--font-weight-medium); }
.settings-row-value { color: var(--color-text-secondary); font-size: var(--font-size-sm); }

.settings-banner {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md);
  background: #fff8e1;
  border-left: 3px solid var(--color-warning);
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-md);
}

/* ── Account delete page ─────────────────────────────────────────────── */
.delete-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg) var(--space-md);
}

.delete-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  width: 100%;
  max-width: 480px;
}

.delete-logo {
  text-align: center;
  margin-bottom: var(--space-lg);
}

.delete-heading {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 var(--space-sm);
  color: var(--color-text);
}

.delete-subtext {
  color: var(--color-text-muted);
  margin: 0 0 var(--space-md);
  font-size: 0.9375rem;
}

.delete-consequences {
  margin: 0 0 var(--space-md);
  padding-left: var(--space-lg);
  color: var(--color-text);
  line-height: 1.6;
}

.delete-notice {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin: 0 0 var(--space-sm);
}

.delete-warning {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-danger, #c0392b);
  margin: 0 0 var(--space-lg);
}

.delete-blocked {
  background: #fff3cd;
  border: 1px solid #ffc107;
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-lg);
}

.delete-actions {
  display: flex;
  gap: var(--space-sm);
  flex-direction: column;
}

@media (min-width: 400px) {
  .delete-actions {
    flex-direction: row;
  }

  .delete-actions .btn {
    flex: 1;
  }
}

.btn-danger {
  background: var(--color-danger, #c0392b);
  color: #fff;
  border: 2px solid var(--color-danger, #c0392b);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  text-align: center;
  text-decoration: none;
  display: inline-block;
}

.btn-danger:hover {
  opacity: 0.9;
}

.delete-success-icon {
  font-size: 3rem;
  color: #27ae60;
  text-align: center;
  margin-bottom: var(--space-sm);
}

/* ── Utility classes ─────────────────────────────────────────────────── */
.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;
}

.text-center { text-align: center; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }


/* ── Pending agreements page ─────────────────────────────────────────── */
.agreement-section {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
}

.agreement-details {
  margin-bottom: var(--space-sm);
}

.agreement-summary {
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.agreement-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.agreement-fulltext {
  margin-top: var(--space-sm);
  padding: var(--space-sm);
  background: var(--color-surface);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-sm);
  max-height: 200px;
  overflow-y: auto;
  white-space: pre-wrap;
}

.agreement-checkbox-label {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  font-size: var(--font-size-sm);
  cursor: pointer;
}

.agreement-checkbox {
  margin-top: 2px;
  flex-shrink: 0;
}