/* ═══════════════════════════════════════════════════════════════════════════
   EVIDENT — Shared Button System
   4 variants (primary, secondary, ghost, danger) × 3 sizes (sm, md, lg)
   All buttons pass WCAG 2.1 AA contrast, have :focus-visible and :disabled.
   Tokens sourced from /assets/css/tokens.css.
   ═══════════════════════════════════════════════════════════════════════════ */

/* ── Base – Touch-safe boundaries (44px minimum on mobile) ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.5rem;
  font-family: var(--font-sans);
  font-size: var(--type-base);
  font-weight: var(--font-weight-semibold);
  line-height: 1;
  text-decoration: none;
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  white-space: nowrap;
  min-height: 2.75rem;
  min-width: 2.75rem;
  transition:
    background var(--duration-fast) var(--ease-out),
    color var(--duration-fast) var(--ease-out),
    border-color var(--duration-fast) var(--ease-out),
    box-shadow var(--duration-normal) var(--ease-out),
    transform var(--duration-fast) var(--ease-out);
  box-sizing: border-box;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent, #f7b32b);
  outline-offset: 3px;
  box-shadow: 0 0 0 5px rgb(247 179 43 / 18%);
}

.btn:active {
  transform: translateY(0) scale(0.97);
  transition-duration: 80ms;
}

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* ── Primary — Sapphire ─────────────────────────────────────── */
.btn--primary {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}

.btn--primary:hover {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  box-shadow:
    0 8px 28px rgb(31 58 153 / 22%),
    0 0 0 1px rgb(31 58 153 / 8%);
  transform: translateY(-2px);
}

/* ── Secondary — Outlined ───────────────────────────────────── */
.btn--secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--border-default);
}

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

/* ── Ghost — Minimal ────────────────────────────────────────── */
.btn--ghost {
  background: transparent;
  color: var(--color-primary);
  border-color: transparent;
}

.btn--ghost:hover {
  background: color-mix(in srgb, var(--color-primary) 8%, transparent);
}

/* ── Danger — Ruby ──────────────────────────────────────────── */
.btn--danger {
  background: var(--color-ruby);
  color: #fff;
  border-color: var(--color-ruby);
}

.btn--danger:hover {
  background: color-mix(in srgb, var(--color-ruby) 85%, black);
  border-color: color-mix(in srgb, var(--color-ruby) 85%, black);
  box-shadow: 0 8px 28px rgb(155 0 32 / 22%);
  transform: translateY(-2px);
}

/* ── Light variant (for dark backgrounds) ───────────────────── */
.btn--light {
  color: var(--ev-text-inverse, #f0ece8);
  border-color: rgb(255 255 255 / 30%);
}

.btn--light:hover {
  border-color: #fff;
  color: #fff;
}

/* ── Sizes ──────────────────────────────────────────────────── */
.btn--sm {
  padding: 0.5rem 1rem;
  font-size: var(--type-sm);
  border-radius: var(--radius-sm);
  min-height: 2.5rem;
}

.btn--lg {
  padding: 1rem 1.75rem;
  font-size: 1.0625rem;
  min-height: 2.75rem;
}

/* ── Full width ─────────────────────────────────────────────── */
.btn--full {
  width: 100%;
}

/* ── Reduced motion ─────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .btn {
    transition: none;
  }
}