/* Design System Tokens */
:root {
  /* Colors - Light Mode */
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-surface-hover: #f5f5f5;
  --color-border: #e5e5e5;
  --color-text-primary: #0a0a0a;
  --color-text-secondary: #525252;
  --color-text-tertiary: #a3a3a3;
  --color-accent: #0a0a0a;
  --color-accent-hover: #262626;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', 'Consolas', monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 4px 8px rgba(0, 0, 0, 0.08);
  --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.04), 0 4px 12px rgba(0, 0, 0, 0.04);
  --shadow-card-hover: 0 2px 6px rgba(0, 0, 0, 0.06), 0 8px 24px rgba(0, 0, 0, 0.08);

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

/* Dark Mode */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #0a0a0a;
    --color-surface: #171717;
    --color-surface-hover: #262626;
    --color-border: #262626;
    --color-text-primary: #fafafa;
    --color-text-secondary: #a3a3a3;
    --color-text-tertiary: #525252;
    --color-accent: #fafafa;
    --color-accent-hover: #d4d4d4;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 4px 8px rgba(0, 0, 0, 0.4);
    --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.2), 0 4px 12px rgba(0, 0, 0, 0.2);
    --shadow-card-hover: 0 2px 6px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.3);
  }
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.5;
  min-height: 100vh;
}

/* Container */
.container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-xl);
}

/* Header */
.header {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.brand {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--color-text-primary);
  margin-bottom: var(--space-xs);
}

.subtitle {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
}

/* Cards */
.cards {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  width: 100%;
  max-width: 480px;
}

.card {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg) var(--space-xl);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: inherit;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-card);
}

.card:hover {
  background-color: var(--color-surface-hover);
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.card:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.card-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-bg);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
}

.card-content {
  flex: 1;
  min-width: 0;
}

.card-title {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--color-text-primary);
  margin-bottom: var(--space-xs);
}

.card-tagline {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.4;
}

.card-arrow {
  flex-shrink: 0;
  color: var(--color-text-tertiary);
  transition: all var(--transition-fast);
}

.card:hover .card-arrow {
  color: var(--color-text-primary);
  transform: translateX(4px);
}

/* Footer */
.footer {
  margin-top: var(--space-3xl);
  text-align: center;
}

.footer p {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-tertiary);
  letter-spacing: 0.04em;
}

/* Responsive */
@media (min-width: 640px) {
  .brand {
    font-size: 2rem;
  }

  .cards {
    gap: var(--space-lg);
  }

  .card {
    padding: var(--space-xl) var(--space-2xl);
  }
}

@media (min-width: 768px) {
  .cards {
    flex-direction: row;
    max-width: 640px;
  }

  .card {
    flex: 1;
    flex-direction: column;
    align-items: flex-start;
    text-align: left;
    padding: var(--space-2xl);
  }

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

  .card-arrow {
    position: absolute;
    top: var(--space-xl);
    right: var(--space-xl);
  }

  .card {
    position: relative;
  }
}

/* Animations */
@media (prefers-reduced-motion: no-preference) {
  .card {
    transition: all var(--transition-slow);
  }

  .card:hover {
    transform: translateY(-4px);
  }

  .card-arrow {
    transition: all var(--transition-base);
  }

  .card:hover .card-arrow {
    transform: translateX(6px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .card,
  .card-arrow {
    transition: none;
  }

  .card:hover {
    transform: none;
  }
}

/* ---- View State Machine ---- */
.view {
  display: none;
  opacity: 0;
}

.view.active {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 1;
}

@media (prefers-reduced-motion: no-preference) {
  .view.active {
    /* var(--transition-slow) already expands to a timing function; adding
       another (e.g. "ease") makes the shorthand invalid and the browser
       silently drops the animation, leaving the view at opacity:0. */
    animation: fadeIn var(--transition-slow) forwards;
  }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

@media (prefers-reduced-motion: reduce) {
  .view.active {
    animation: none;
    opacity: 1;
  }
}

/* ---- Login Card ---- */
.login-card {
  width: 100%;
  max-width: 24rem;
  padding: var(--space-xl);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 0;
}

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

.login-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  padding: var(--space-xs) var(--space-sm);
  border: 1px solid var(--color-border);
  line-height: 1;
}

.login-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
}

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

.login-field-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
}

.login-input {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 0;
  color: var(--color-text-primary);
  outline: none;
  transition: border-color var(--transition-fast);
}

.login-input::placeholder {
  color: var(--color-text-tertiary);
}

.login-input:focus {
  border-color: var(--color-accent);
}

.login-error {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #dc2626;
  min-height: 1rem;
}

@media (prefers-color-scheme: dark) {
  .login-error {
    color: #ef4444;
  }
}

.login-button {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-style: italic;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
  padding: var(--space-md) var(--space-lg);
  margin-top: var(--space-sm);
  background-color: var(--color-accent);
  color: var(--color-surface);
  border: none;
  border-radius: 0;
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.login-button:hover {
  background-color: var(--color-accent-hover);
}

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

.login-link {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  text-align: center;
  margin-top: var(--space-md);
  text-decoration: underline;
  text-underline-offset: 2px;
  transition: color var(--transition-fast);
}

.login-link:hover {
  color: var(--color-text-primary);
}

/* ---- Logout ---- */
.logout-button {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-tertiary);
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 0;
  padding: var(--space-xs) var(--space-md);
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  margin-top: var(--space-xl);
}

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

/* ---- Error / Connection State ---- */
.error-card {
  width: 100%;
  max-width: 24rem;
  padding: var(--space-xl);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 0;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
}

.error-text {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-primary);
}

.error-detail {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  letter-spacing: 0.04em;
}