/* ============================================================
   design-system.css
   Single source of truth for all visual tokens and shared
   component classes.

   Load this file BEFORE all other stylesheets.
   Run: bash tests/design-system-check.sh to verify consistency.
   ============================================================ */

/* ── CSS Custom Properties (tokens) ─────────────────────────── */
:root {

  /* Color palette */
  --color-primary: #6366f1;
  --color-primary-hover: #4f46e5;
  --color-primary-light: rgba(99, 102, 241, 0.12);
  --color-danger: #ef4444;
  --color-danger-light: rgba(239, 68, 68, 0.1);
  --color-success: #22c55e;
  --color-success-light: rgba(34, 197, 94, 0.1);
  --color-warning: #f59e0b;
  --color-warning-light: rgba(245, 158, 11, 0.1);
  --color-text-primary: #111827;
  --color-text-secondary: #6b7280;
  --color-text-muted: #9ca3af;
  --color-bg-primary: #ffffff;
  --color-bg-secondary: #f9fafb;
  --color-bg-surface: #f3f4f6;
  --color-border: #e5e7eb;

  /* Spacing scale */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;

  /* Type scale (rem only) */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;

  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
}

/* ── Button System ───────────────────────────────────────────── */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  cursor: pointer;
  border: 1px solid transparent;
  text-decoration: none;
  white-space: nowrap;
  transition: background 150ms ease, color 150ms ease, border-color 150ms ease, opacity 150ms ease;
  line-height: 1;
}

/* Size variants */
.btn-sm {
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
}

.btn-md {
  padding: var(--space-2) var(--space-4);
}

.btn-lg {
  padding: var(--space-3) var(--space-5);
  font-size: var(--text-base);
}

/* Color variants */
.btn-primary {
  background: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
}

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

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

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

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

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

.btn-danger {
  background: var(--color-danger);
  color: #ffffff;
  border-color: var(--color-danger);
}

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

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

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

.btn-ghost:hover {
  background: var(--color-bg-surface);
  color: var(--color-text-primary);
}

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

/* ── Badge / Pill System ─────────────────────────────────────── */

.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 500;
  line-height: 1;
  white-space: nowrap;
}

.badge-primary {
  background: color-mix(in srgb, var(--color-primary) 15%, transparent);
  color: var(--color-primary);
}

.badge-danger {
  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
  color: var(--color-danger);
}

.badge-success {
  background: color-mix(in srgb, var(--color-success) 15%, transparent);
  color: var(--color-success);
}

.badge-warning {
  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
  color: var(--color-warning);
}

.badge-neutral {
  background: var(--color-bg-surface);
  color: var(--color-text-secondary);
}

/* Nav notification count badge */
.badge-count {
  min-width: 18px;
  height: 18px;
  padding: 0 var(--space-1);
  text-align: center;
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 600;
  line-height: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* ── Modal / Sheet System ────────────────────────────────────── */

.modal-surface {
  background: var(--color-bg-primary);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-lg);
}

.sheet-surface {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
}

/* ── Input System ────────────────────────────────────────────── */

.input-field {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--color-text-primary);
  background: var(--color-bg-primary);
  transition: border-color 150ms ease, outline 150ms ease;
  box-sizing: border-box;
}

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

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

/* ── Layout ──────────────────────────────────────────────────── */

.page-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-5);
}

@media (max-width: 768px) {
  .page-container {
    padding: 0 var(--space-4);
  }
}