/* ==========================================================================
   Cleo Design System
   A clean, light, minimalist design for a coloring page generator.
   ========================================================================== */

/* --- CSS Variables --- */
:root {
  /* Colors */
  --color-bg: #f5f5f7;
  --color-surface: #ffffff;
  --color-primary: #7c5cbf;
  --color-primary-hover: #6a4daa;
  --color-primary-active: #5a3f96;
  --color-secondary: #e8e0f3;
  --color-secondary-hover: #ddd2ed;
  --color-secondary-text: #5a3f96;
  --color-text: #4a2d7a;
  --color-text-muted: #a88bcc;
  --color-border: #d2d2d7;
  --color-border-focus: #7c5cbf;
  --color-error: #d32f2f;
  --color-error-bg: #fdecea;
  --color-success: #2e7d32;
  --color-success-bg: #edf7ee;

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

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    Oxygen, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.5rem;
  --font-size-2xl: 2rem;
  --font-size-3xl: 2.5rem;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --line-height: 1.6;

  /* Borders & Shadows */
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-full: 9999px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08), 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.1), 0 4px 8px rgba(0, 0, 0, 0.04);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
}

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

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

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height);
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-hover);
}

img {
  max-width: 100%;
  display: block;
}

/* --- Layout --- */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container--narrow {
  max-width: 480px;
}

.container--wide {
  max-width: 1400px;
}

/* --- Navigation --- */
.nav {
  background: #fff;
  border-bottom: 1px solid #eee;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
  padding: 0 24px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  padding: 8px 16px;
  border-radius: 8px;
  text-decoration: none;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
  border: none;
  background: none;
  cursor: pointer;
}

.nav-link:hover {
  background: #f5f5f5;
  color: var(--color-text);
}

.nav-link.active {
  background: #f0f0f0;
  color: var(--color-text);
}

.nav-remaining {
  padding: 6px 14px;
  background: var(--color-secondary);
  color: var(--color-primary);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  white-space: nowrap;
}

.btn-logout {
  padding: 8px 16px;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
  background: #fff;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}

.btn-logout:hover {
  background: #f5f5f5;
  border-color: #ccc;
}

/* --- Card --- */
.card {
  background-color: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: var(--space-xl);
}

.card--flat {
  box-shadow: none;
  border: 1px solid var(--color-border);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.5rem;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  line-height: 1;
  color: #ffffff;
  background-color: var(--color-primary);
  border: 2px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast),
    box-shadow var(--transition-fast), transform var(--transition-fast);
  user-select: none;
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  background-color: var(--color-primary-hover);
  box-shadow: var(--shadow-sm);
}

.btn:active {
  background-color: var(--color-primary-active);
  transform: translateY(1px);
  box-shadow: none;
}

.btn:focus-visible {
  outline: 3px solid var(--color-secondary);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.btn--full {
  width: 100%;
}

.btn-secondary {
  color: var(--color-secondary-text);
  background-color: transparent;
  border-color: var(--color-border);
}

.btn-secondary:hover {
  background-color: var(--color-secondary);
  border-color: var(--color-secondary-hover);
}

.btn-secondary:active {
  background-color: var(--color-secondary-hover);
}

.btn--small {
  padding: 0.5rem 1rem;
  font-size: var(--font-size-sm);
}

.btn--danger {
  background-color: var(--color-error);
}

.btn--danger:hover {
  background-color: #b71c1c;
}

/* --- Form Inputs --- */
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.form-group + .form-group {
  margin-top: var(--space-md);
}

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

.input {
  width: 100%;
  padding: 0.75rem 1rem;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  outline: none;
}

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

.input:hover {
  border-color: #b0b0b5;
}

.input:focus {
  border-color: var(--color-border-focus);
  box-shadow: 0 0 0 3px rgba(124, 92, 191, 0.15);
}

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

.input--error:focus {
  box-shadow: 0 0 0 3px rgba(211, 47, 47, 0.15);
}

/* --- Messages --- */
.error-message {
  color: var(--color-error);
  background-color: var(--color-error-bg);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(211, 47, 47, 0.2);
  display: none;
}

.error-message--visible {
  display: block;
}

.success-message {
  color: var(--color-success);
  background-color: var(--color-success-bg);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(46, 125, 50, 0.2);
}

/* --- Loading Spinner --- */
.loading {
  display: inline-block;
  width: 1.25rem;
  height: 1.25rem;
  border: 2.5px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.loading--large {
  width: 2.5rem;
  height: 2.5rem;
  border-width: 3px;
}

.loading--center {
  display: block;
  margin: var(--space-xl) auto;
}

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

/* --- Tabs --- */
.tabs {
  display: flex;
  border-bottom: 2px solid var(--color-border);
  margin-bottom: var(--space-xl);
}

.tab {
  flex: 1;
  padding: var(--space-md) var(--space-lg);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.tab:hover {
  color: var(--color-text);
}

.tab--active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

/* --- Utility --- */
.text-center {
  text-align: center;
}

.text-muted {
  color: var(--color-text-muted);
}

.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }

.hidden {
  display: none !important;
}

/* --- Footer --- */
.site-footer {
  text-align: center;
  padding: var(--space-xl) var(--space-lg);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  border-top: 1px solid var(--color-border);
  margin-top: var(--space-2xl);
}

/* --- Creator Text --- */
.creator-text {
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
  font-style: italic;
}

/* --- Features List --- */
.features-list {
  list-style: none;
  margin: var(--space-lg) 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.features-list li {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  padding-left: 1.4rem;
  position: relative;
  line-height: 1.5;
}

.features-list li::before {
  content: '\2713';
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-weight: var(--font-weight-bold);
}

/* --- Auth Page Specific --- */
.auth-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: var(--space-xl) var(--space-lg);
}

.auth-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.auth-header__title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
  letter-spacing: -0.03em;
}

.auth-header__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
  margin-top: var(--space-xs);
  font-weight: var(--font-weight-normal);
}

.auth-form {
  margin-top: var(--space-lg);
}

.auth-form .btn {
  margin-top: var(--space-lg);
}

/* --- Responsive --- */
@media (max-width: 600px) {
  :root {
    --font-size-3xl: 2rem;
    --font-size-2xl: 1.5rem;
    --font-size-xl: 1.25rem;
  }

  .card {
    padding: var(--space-lg);
    border-radius: var(--radius-md);
  }

  .container {
    padding: 0 var(--space-md);
  }

  .auth-page {
    padding: var(--space-lg) var(--space-md);
  }

  .nav__inner {
    padding: 0 var(--space-md);
  }
}

@media (max-width: 380px) {
  .tab {
    padding: var(--space-sm) var(--space-md);
    font-size: var(--font-size-sm);
  }
}