/* Uplink Access — Identity Presentation Stylesheet */
/* WCAG 2.1 AA Compliant, Server-Rendered, Zero Remote Assets */

:root {
  --color-canvas: #0F172A;       /* Slate 900 */
  --color-surface: #1E293B;      /* Slate 800 */
  --color-card: #FFFFFF;         /* White */
  --color-app-bg: #F8FAFC;       /* Slate 50 */
  --color-border: #E2E8F0;       /* Slate 200 */
  --color-border-focus: #2563EB;  /* Blue 600 */

  --color-text-primary: #0F172A; /* Slate 900 (WCAG AAA >= 12:1) */
  --color-text-muted: #64748B;   /* Slate 500 (WCAG AA >= 4.5:1) */
  --color-text-inverse: #FFFFFF;

  --color-primary: #1E40AF;       /* Blue 800 */
  --color-primary-hover: #1D4ED8; /* Blue 700 */
  --color-error: #B91C1C;         /* Red 700 (WCAG AA >= 4.5:1 on #FEF2F2: 5.91:1) */
  --color-error-bg: #FEF2F2;      /* Red 50 */
  --color-success: #15803D;       /* Green 700 (WCAG AA >= 4.5:1 on #F0FDF4: 4.79:1) */
  --color-success-bg: #F0FDF4;    /* Green 50 */

  --color-info: #0369A1;         /* Sky 700 (WCAG AA >= 4.5:1 on #F0F9FF: 5.57:1) */
  --color-info-bg: #F0F9FF;      /* Sky 50 */
  --color-border-error: #FCA5A5; /* Red 300 */
  --color-border-success: #86EFAC; /* Green 300 */
  --color-border-info: #BAE6FD;  /* Sky 200 */

  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
}

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

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.5;
  color: var(--color-text-primary);
  background-color: var(--color-app-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body.auth-body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--color-app-bg);
  color: var(--color-text-primary);
}

/* Accessible Skip Navigation Link */
.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 14px;
  text-decoration: none;
  z-index: 1000;
  transition: top 150ms ease;
}

.skip-link:focus {
  top: 16px;
  outline: 2px solid var(--color-border-focus);
  outline-offset: 2px;
}

/* Centered Authentication Shell Layout */
.auth-wrapper {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  min-height: 100vh;
  width: 100%;
  padding: 24px 16px;
}

.auth-header {
  width: 100%;
  max-width: 440px;
  margin: 0 auto;
  padding: 24px 0 16px;
  text-align: center;
}

.auth-brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--color-text-primary);
}

.brand-name {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-canvas);
}

.brand-badge {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background-color: var(--color-surface);
  color: var(--color-text-inverse);
  padding: 2px 7px;
  border-radius: var(--radius-sm);
}

.auth-main {
  width: 100%;
  max-width: 440px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
}

.auth-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 4px 6px -1px rgba(15, 23, 42, 0.05), 0 2px 4px -2px rgba(15, 23, 42, 0.05);
  padding: 32px;
  width: 100%;
}

.auth-card-content {
  margin-bottom: 20px;
}

.auth-title {
  margin: 0 0 8px;
  font-size: 22px;
  font-weight: 700;
  color: var(--color-text-primary);
  line-height: 1.3;
}

.auth-subtitle {
  margin: 0;
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.5;
}

.auth-footer {
  width: 100%;
  max-width: 440px;
  margin: 0 auto;
  padding: 16px 0 24px;
  text-align: center;
}

.auth-footer-text {
  margin: 0;
  font-size: 13px;
  color: var(--color-text-muted);
}

/* Alert Partial Styles (Errors, Success, Info, Rate Limits) */
.alert {
  padding: 12px 14px;
  border-radius: var(--radius-md);
  margin-bottom: 20px;
  font-size: 14px;
  line-height: 1.5;
  border: 1px solid transparent;
}

.alert-message {
  margin: 0;
}

.alert-error {
  background-color: var(--color-error-bg);
  border-color: var(--color-border-error);
  color: var(--color-error);
  border-left: 4px solid var(--color-error);
}

.alert-success {
  background-color: var(--color-success-bg);
  border-color: var(--color-border-success);
  color: var(--color-success);
  border-left: 4px solid var(--color-success);
}

.alert-info {
  background-color: var(--color-info-bg);
  border-color: var(--color-border-info);
  color: var(--color-info);
  border-left: 4px solid var(--color-info);
}

/* Form Styles */
.auth-form {
  display: flex;
  flex-direction: column;
  width: 100%;
}

.form-group {
  display: flex;
  flex-direction: column;
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 6px;
}

.form-label-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  height: 42px;
  padding: 8px 12px;
  font-size: 14px;
  font-family: inherit;
  color: var(--color-text-primary);
  background-color: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color 150ms ease, box-shadow 150ms ease;
}

.form-input:focus {
  outline: 2px solid var(--color-border-focus);
  outline-offset: 1px;
  border-color: var(--color-border-focus);
}

.form-input-error {
  border-color: var(--color-error);
}

.form-input-error:focus {
  outline: 2px solid var(--color-error);
  outline-offset: 1px;
  border-color: var(--color-error);
}

.field-help {
  margin: 6px 0 0;
  font-size: 13px;
  color: var(--color-text-muted);
  line-height: 1.4;
}

.field-error {
  margin: 6px 0 0;
  font-size: 13px;
  font-weight: 500;
  color: var(--color-error);
  line-height: 1.4;
}

/* Button & Action Styles */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 42px;
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 600;
  font-family: inherit;
  border-radius: var(--radius-md);
  cursor: pointer;
  text-decoration: none;
  text-align: center;
  transition: background-color 150ms ease, border-color 150ms ease;
}

.button-primary {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  border: 1px solid var(--color-primary);
}

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

.button-primary:focus-visible {
  outline: 2px solid var(--color-border-focus);
  outline-offset: 2px;
}

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

.button-secondary:hover {
  background-color: var(--color-app-bg);
  border-color: var(--color-primary);
}

.button-secondary:focus-visible {
  outline: 2px solid var(--color-border-focus);
  outline-offset: 2px;
}

/* Links */
.link {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
}

.link:hover {
  text-decoration: underline;
}

.link:focus-visible {
  outline: 2px solid var(--color-border-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.link-subtle {
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
}

.link-subtle:hover {
  text-decoration: underline;
}

.link-subtle:focus-visible {
  outline: 2px solid var(--color-border-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Card Footer & Auxiliary Components */
.auth-card-footer {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: 14px;
  color: var(--color-text-muted);
}

.auth-card-footer p {
  margin: 0;
}

.auth-card-actions {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.notice-box {
  background-color: var(--color-app-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 16px;
  margin: 16px 0 24px;
  font-size: 14px;
  color: var(--color-text-primary);
  line-height: 1.5;
}

.notice-box p {
  margin: 0;
}

.auth-icon-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: var(--color-app-bg);
  color: var(--color-text-muted);
  margin-bottom: 16px;
  border: 1px solid var(--color-border);
}

/* Responsive & Narrow-Width Strategy */
@media (max-width: 480px) {
  .auth-wrapper {
    padding: 16px 12px;
  }

  .auth-card {
    padding: 24px 16px;
  }

  .auth-title {
    font-size: 20px;
  }
}

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