/* a11y.css — small, focused accessibility baseline (Polish 12.6, 2026-04-27).
 *
 * Loaded once via header.php so it covers every page that pulls the
 * shared header (which is every public/customer/admin surface). Strict
 * CSP-compliant: external stylesheet, nonce-tagged via the <link>.
 *
 * Goals:
 *   - Visible focus ring on every interactive element for keyboard users.
 *     Browsers' default outline is removed by many CSS resets; we restore
 *     a consistent token-based ring on :focus-visible only (so mouse
 *     clicks don't show the ring).
 *   - .sr-only utility class for "visible" labels that should reach
 *     screen readers but not consume visual layout. Pattern from
 *     https://www.tpgi.com/the-anatomy-of-visually-hidden/.
 *   - Skip-link helper that becomes visible on focus.
 *   - Respect for prefers-reduced-motion: any element opted-in via
 *     [data-motion-respect] gets transition/animation suppressed.
 */

:where(a, button, [role="button"], input, select, textarea, [tabindex]:not([tabindex="-1"])):focus-visible {
    outline: 2px solid var(--ui-focus-ring, #2563eb);
    outline-offset: 2px;
    box-shadow: 0 0 0 4px var(--ui-focus-shadow, rgba(37, 99, 235, 0.22));
}

/* Visually hidden, but available to screen readers and assistive tech. */
.sr-only {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}

/* Skip link: hidden until keyboard-focused, then surfaces over the page
 * so keyboard users can jump past the header to the main content. */
.skip-link {
    position: absolute;
    top: -40px;
    left: 8px;
    z-index: 9999;
    padding: 8px 12px;
    background: var(--ui-surface, #fff);
    color: var(--ui-text, #1f2328);
    border: 2px solid var(--ui-focus-ring, #2563eb);
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: top 0.15s ease-out;
}
.skip-link:focus,
.skip-link:focus-visible {
    top: 8px;
}

/* Respect prefers-reduced-motion. Suppresses transitions and animations
 * on elements that opt in via data-motion-respect; doesn't blanket-kill
 * everything. */
@media (prefers-reduced-motion: reduce) {
    [data-motion-respect],
    [data-motion-respect] *,
    .reservation-busy-slots,
    .reservation-busy-slots * {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
        scroll-behavior: auto !important;
    }
}

/* Modal dialogs: the modal-box container should expose a clear focus
 * boundary when focused via the focus-trap fallback path. */
[role="dialog"]:focus-visible,
[role="dialog"][tabindex]:focus {
    outline: 3px solid var(--ui-focus-ring, #2563eb);
    outline-offset: -3px;
}