/* ==========================================================================
   Najibul TOC — Shared + Frontend Stylesheet
   Version: 10.0.0
   File: blocks/toc-block/toc-frontend.css
   Loaded on both editor preview and frontend.
   Editor chrome lives in toc-editor.css.
   ==========================================================================
 *
 * Architecture (v10.0.0):
 *   - Semantic HTML5: <nav> wrapper, <h2>-<h6> title, <ol><li><a> list
 *   - Accessibility: aria-expanded button, focus-visible rings,
 *                    prefers-reduced-motion, prefers-contrast
 *   - RTL-aware: logical properties (inset-inline, margin-inline)
 *   - Dark mode: prefers-color-scheme auto-adaptation
 *   - Print-aware: anchor hidden, layout preserved
 *   - Zero global leaks: @layer scoped
 *
 * Sections:
 *    1. Design tokens
 *    2. Dark mode tokens
 *    3. Wrapper (nav.najibul-toc-wrapper)
 *    4. Container (.najibul-toc)
 *    5. Header (.najibul-toc-header)
 *    6. Title (h2-h6 .najibul-toc-title)
 *    7. Toggle button (.najibul-toc-toggle)
 *    8. Body (.najibul-toc-body)
 *    9. List (.najibul-toc-list)
 *   10. Item (.najibul-toc-item)
 *   11. Link (.najibul-toc-link)
 *   12. Marker (.najibul-toc-marker)
 *   13. Active state (ScrollSpy)
 *   14. Collapsed state
 *   15. Empty state
 *   16. Responsive — tablet
 *   17. Responsive — mobile
 *   18. RTL
 *   19. Dark mode — extras
 *   20. Print
 *   21. Accessibility
 *   22. Editor preview consistency
 */

@layer najibul-toc {

/* ═══════════════════════════════════════════════════════════════════
 * 1. DESIGN TOKENS
 * ═══════════════════════════════════════════════════════════════════ */

:where(.najibul-toc-wrapper) {
    /* Colors — overridable per block instance via inline CSS vars */
    --toc-bg:              #ffffff;
    --toc-border:          #e2e8f0;
    --toc-text:            #475569;
    --toc-heading:         #0f172a;
    --toc-radius:          12px;

    /* Derived colors */
    --toc-text-strong:     #0f172a;
    --toc-text-muted:      #94a3b8;
    --toc-border-light:    #f1f5f9;
    --toc-border-strong:   #cbd5e1;

    /* Accent (fixed — not configurable) */
    --toc-accent:          #3b82f6;
    --toc-accent-soft:     rgba(59, 130, 246, 0.08);
    --toc-accent-ring:     rgba(59, 130, 246, 0.25);

    /* Shadows */
    --toc-shadow-xs:       0 1px 2px rgba(15, 23, 42, 0.04);
    --toc-shadow-sm:       0 2px 8px rgba(15, 23, 42, 0.04);
    --toc-shadow-md:       0 4px 20px rgba(15, 23, 42, 0.06);
    --toc-shadow-lg:       0 10px 30px rgba(15, 23, 42, 0.08);

    /* Spacing scale */
    --toc-space-xs:        4px;
    --toc-space-sm:        8px;
    --toc-space-md:        16px;
    --toc-space-lg:        24px;
    --toc-space-xl:        32px;

    /* Typography */
    --toc-font:            -apple-system, BlinkMacSystemFont, "Segoe UI",
                           Roboto, "Helvetica Neue", Arial, sans-serif;

    --toc-font-xs:         12px;
    --toc-font-sm:         14px;
    --toc-font-base:       15px;
    --toc-font-lg:         17px;

    /* Motion */
    --toc-ease:            cubic-bezier(0.4, 0, 0.2, 1);
    --toc-t-fast:          150ms cubic-bezier(0.4, 0, 0.2, 1);
    --toc-t-base:          250ms cubic-bezier(0.4, 0, 0.2, 1);
    --toc-t-slow:          400ms cubic-bezier(0.4, 0, 0.2, 1);
}


/* ═══════════════════════════════════════════════════════════════════
 * 2. DARK MODE TOKENS
 * ═══════════════════════════════════════════════════════════════════ */

@media (prefers-color-scheme: dark) {
    :where(.najibul-toc-wrapper:not(.no-dark-mode)) {
        --toc-bg:              #0f172a;
        --toc-border:          #334155;
        --toc-text:            #cbd5e1;
        --toc-heading:         #f1f5f9;

        --toc-text-strong:     #f8fafc;
        --toc-text-muted:      #64748b;
        --toc-border-light:    #1e293b;
        --toc-border-strong:   #475569;

        --toc-accent-soft:     rgba(96, 165, 250, 0.12);
        --toc-accent-ring:     rgba(96, 165, 250, 0.35);

        --toc-shadow-xs:       0 1px 2px rgba(0, 0, 0, 0.30);
        --toc-shadow-sm:       0 2px 8px rgba(0, 0, 0, 0.40);
        --toc-shadow-md:       0 4px 20px rgba(0, 0, 0, 0.50);
        --toc-shadow-lg:       0 10px 30px rgba(0, 0, 0, 0.60);
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 3. WRAPPER (nav.najibul-toc-wrapper)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-wrapper {
    display: block;
    inline-size: 100%;
    max-inline-size: 800px;
    margin-block: 40px;
    margin-inline: auto;
    padding: 0;
    box-sizing: border-box;
    float: none;
    clear: both;
    font-family: var(--toc-font);
    color: var(--toc-text);
    /* Prevent sub-pixel overflow jitter */
    isolation: isolate;
}

.najibul-toc-wrapper *,
.najibul-toc-wrapper *::before,
.najibul-toc-wrapper *::after {
    box-sizing: border-box;
}


/* ═══════════════════════════════════════════════════════════════════
 * 4. CONTAINER (.najibul-toc)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc {
    display: block;
    background: var(--toc-bg);
    border: 1px solid var(--toc-border);
    border-radius: var(--toc-radius);
    overflow: hidden;
    box-shadow: var(--toc-shadow-sm);
    transition:
        box-shadow var(--toc-t-base),
        border-color var(--toc-t-base);
}

.najibul-toc:hover {
    box-shadow: var(--toc-shadow-md);
    border-color: var(--toc-border-strong);
}


/* ═══════════════════════════════════════════════════════════════════
 * 5. HEADER (.najibul-toc-header)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--toc-space-md);
    padding-block: 18px;
    padding-inline: 24px;
    background: var(--toc-bg);
    border-block-end: 1px solid var(--toc-border);
    transition:
        background var(--toc-t-base),
        border-color var(--toc-t-base);
}

.najibul-toc-header:hover {
    background: var(--toc-accent-soft);
}


/* ═══════════════════════════════════════════════════════════════════
 * 6. TITLE (semantic h2-h6)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-title {
    display: flex;
    align-items: center;
    gap: 12px;
    margin: 0;
    padding: 0;
    color: var(--toc-heading);
    font-family: var(--toc-font);
    font-weight: 700;
    line-height: 1.35;
    letter-spacing: -0.3px;
    flex: 1;
    min-inline-size: 0;
    overflow-wrap: break-word;
}

/* Base scale — applied regardless of heading level */
h2.najibul-toc-title { font-size: var(--toc-font-lg); }
h3.najibul-toc-title { font-size: calc(var(--toc-font-lg) * 0.95); }
h4.najibul-toc-title { font-size: calc(var(--toc-font-lg) * 0.9); }
h5.najibul-toc-title { font-size: calc(var(--toc-font-lg) * 0.85); }
h6.najibul-toc-title { font-size: calc(var(--toc-font-lg) * 0.8); }

.najibul-toc-title-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1em;
    line-height: 1;
}

.najibul-toc-title-text {
    flex: 1;
    min-inline-size: 0;
    white-space: normal;
    overflow-wrap: break-word;
}


/* ═══════════════════════════════════════════════════════════════════
 * 7. TOGGLE BUTTON (.najibul-toc-toggle)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    inline-size: 32px;
    block-size: 32px;
    min-inline-size: 32px;
    padding: 0;
    background: transparent;
    color: var(--toc-heading);
    border: 1px solid transparent;
    border-radius: var(--toc-space-sm);
    cursor: pointer;
    flex-shrink: 0;
    transition:
        background var(--toc-t-fast),
        border-color var(--toc-t-fast),
        transform var(--toc-t-base);
    -webkit-tap-highlight-color: transparent;
    outline: none;
}

.najibul-toc-toggle:hover {
    background: var(--toc-accent-soft);
    border-color: var(--toc-accent-ring);
}

.najibul-toc-toggle:active {
    transform: scale(0.94);
}

.najibul-toc-toggle:focus-visible {
    outline: 2px solid var(--toc-accent);
    outline-offset: 2px;
    border-radius: var(--toc-space-sm);
}

.najibul-toc-toggle svg {
    display: block;
    inline-size: 16px;
    block-size: 16px;
    transition: transform var(--toc-t-base);
    transform: rotate(0deg);
    flex-shrink: 0;
}

/* Arrow flips when collapsed */
.najibul-toc-wrapper.is-collapsed .najibul-toc-toggle svg {
    transform: rotate(180deg);
}


/* ═══════════════════════════════════════════════════════════════════
 * 8. BODY (.najibul-toc-body)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-body {
    display: block;
    padding-block: var(--toc-space-md) var(--toc-space-lg);
    padding-inline: var(--toc-space-lg);
    background: var(--toc-bg);
}

/* Fallback for browsers that ignore `[hidden]` + display: block */
.najibul-toc-body[hidden] {
    display: none !important;
}


/* ═══════════════════════════════════════════════════════════════════
 * 9. LIST (.najibul-toc-list) — semantic <ol>
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 0;
    padding: 0;
    list-style: none;
}


/* ═══════════════════════════════════════════════════════════════════
 * 10. ITEM (.najibul-toc-item)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-item {
    margin: 0;
    padding: 0;
    position: relative;
}


/* ═══════════════════════════════════════════════════════════════════
 * 11. LINK (.najibul-toc-link)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-link {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding-block: 6px;
    padding-inline: 8px;
    margin-inline: -8px;
    color: var(--toc-text);
    text-decoration: none;
    border-radius: var(--toc-space-sm);
    font-size: var(--toc-font-base);
    font-weight: 500;
    line-height: 1.5;
    transition:
        color var(--toc-t-fast),
        background-color var(--toc-t-fast),
        padding-inline-start var(--toc-t-base);
    outline: none;
}

.najibul-toc-link:hover {
    color: var(--toc-heading);
    background: var(--toc-accent-soft);
    padding-inline-start: 14px;
}

.najibul-toc-link:focus-visible {
    outline: 2px solid var(--toc-accent);
    outline-offset: 2px;
    color: var(--toc-heading);
}


/* ═══════════════════════════════════════════════════════════════════
 * 12. MARKER (.najibul-toc-marker)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-marker {
    display: inline-block;
    inline-size: 6px;
    block-size: 6px;
    min-inline-size: 6px;
    margin-block-start: 9px;
    background: var(--toc-text);
    border-radius: 50%;
    opacity: 0.4;
    flex-shrink: 0;
    transition:
        opacity var(--toc-t-fast),
        transform var(--toc-t-base),
        background-color var(--toc-t-fast);
}

.najibul-toc-link:hover .najibul-toc-marker {
    opacity: 1;
    transform: scale(1.3);
    background: var(--toc-accent);
}


/* ═══════════════════════════════════════════════════════════════════
 * 13. ACTIVE STATE (ScrollSpy)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-link.active {
    color: var(--toc-accent);
    background: var(--toc-accent-soft);
    font-weight: 600;
    padding-inline-start: 14px;
}

.najibul-toc-link.active .najibul-toc-marker {
    opacity: 1;
    transform: scale(1.3);
    background: var(--toc-accent);
}


/* ═══════════════════════════════════════════════════════════════════
 * 14. COLLAPSED STATE
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-wrapper.is-collapsed .najibul-toc-header {
    border-block-end-color: transparent;
}


/* ═══════════════════════════════════════════════════════════════════
 * 15. EMPTY STATE (editor only — silent on frontend)
 * ═══════════════════════════════════════════════════════════════════ */

.najibul-toc-empty .najibul-toc-header {
    border-block-end: 1px solid var(--toc-border);
}

.najibul-toc-empty-message {
    margin: 0;
    padding-block: 12px;
    padding-inline: 8px;
    color: var(--toc-text-muted);
    font-size: var(--toc-font-sm);
    font-style: italic;
    text-align: center;
    line-height: 1.5;
}


/* ═══════════════════════════════════════════════════════════════════
 * 16. RESPONSIVE — TABLET (≤ 900px)
 * ═══════════════════════════════════════════════════════════════════ */

@media (max-width: 900px) {
    .najibul-toc-wrapper {
        margin-block: var(--toc-space-xl);
        margin-inline: 0;
        max-inline-size: 100%;
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 17. RESPONSIVE — SMALL TABLET (≤ 768px)
 * ═══════════════════════════════════════════════════════════════════ */

@media (max-width: 768px) {
    .najibul-toc-wrapper {
        margin-block: 25px;
    }

    .najibul-toc-header {
        padding-block: 15px;
        padding-inline: 20px;
    }

    h2.najibul-toc-title,
    h3.najibul-toc-title,
    h4.najibul-toc-title,
    h5.najibul-toc-title,
    h6.najibul-toc-title {
        font-size: 16px;
    }

    .najibul-toc-body {
        padding-block: 14px 20px;
        padding-inline: 20px;
    }

    .najibul-toc-link {
        font-size: var(--toc-font-sm);
        gap: 10px;
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 17b. RESPONSIVE — MOBILE (≤ 480px)
 * ═══════════════════════════════════════════════════════════════════ */

@media (max-width: 480px) {
    .najibul-toc-wrapper {
        margin-block: 20px;
    }

    .najibul-toc-header {
        padding-block: 12px;
        padding-inline: 16px;
    }

    h2.najibul-toc-title,
    h3.najibul-toc-title,
    h4.najibul-toc-title,
    h5.najibul-toc-title,
    h6.najibul-toc-title {
        font-size: 15px;
        gap: 8px;
    }

    .najibul-toc-body {
        padding-block: 12px 16px;
        padding-inline: 16px;
    }

    .najibul-toc-link {
        font-size: 13px;
        gap: 8px;
        padding-block: 5px;
    }

    .najibul-toc-marker {
        inline-size: 5px;
        block-size: 5px;
        min-inline-size: 5px;
        margin-block-start: 8px;
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 18. RTL
 * ═══════════════════════════════════════════════════════════════════ */

[dir="rtl"] .najibul-toc-link {
    text-align: right;
}

[dir="rtl"] .najibul-toc-link:hover,
[dir="rtl"] .najibul-toc-link.active {
    padding-inline-start: 8px;
    padding-inline-end: 14px;
}

[dir="rtl"] .najibul-toc-title {
    text-align: right;
}

[dir="rtl"] .najibul-toc-marker {
    /* Mirror order handled by flex direction being auto in RTL */
}

[dir="rtl"] .najibul-toc-toggle svg {
    transform: rotate(0deg);
}

[dir="rtl"] .najibul-toc-wrapper.is-collapsed .najibul-toc-toggle svg {
    transform: rotate(180deg);
}


/* ═══════════════════════════════════════════════════════════════════
 * 19. DARK MODE — EXTRAS
 * ═══════════════════════════════════════════════════════════════════ */

@media (prefers-color-scheme: dark) {
    .najibul-toc-wrapper:not(.no-dark-mode) .najibul-toc-header:hover {
        background: var(--toc-accent-soft);
    }

    .najibul-toc-wrapper:not(.no-dark-mode) .najibul-toc-link:hover {
        background: var(--toc-accent-soft);
    }

    .najibul-toc-wrapper:not(.no-dark-mode) .najibul-toc-toggle:hover {
        background: var(--toc-accent-soft);
        border-color: var(--toc-accent-ring);
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 20. PRINT
 * ═══════════════════════════════════════════════════════════════════ */

@media print {
    .najibul-toc-wrapper {
        max-inline-size: 100% !important;
        margin-block: 20px !important;
        margin-inline: 0 !important;
        page-break-inside: avoid;
    }

    .najibul-toc {
        border: 1px solid #cbd5e1 !important;
        box-shadow: none !important;
        break-inside: avoid;
    }

    .najibul-toc-toggle {
        display: none !important;
    }

    .najibul-toc-body {
        display: block !important;
        padding: 12px 16px 16px !important;
    }

    .najibul-toc-body[hidden] {
        display: block !important;
    }

    .najibul-toc-link {
        color: #0f172a !important;
        page-break-inside: avoid;
    }

    .najibul-toc-link:hover,
    .najibul-toc-link.active {
        background: transparent !important;
        color: #0f172a !important;
    }

    .najibul-toc-marker {
        background: #475569 !important;
        opacity: 0.7 !important;
    }

    .najibul-toc-title {
        color: #0f172a !important;
    }

    /* Hide TOC entirely if block-level print is disabled */
    .najibul-toc-wrapper.no-print {
        display: none !important;
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 21. ACCESSIBILITY
 * ═══════════════════════════════════════════════════════════════════ */

/* High contrast preference — increase border + text strength */
@media (prefers-contrast: high) {
    .najibul-toc-wrapper {
        --toc-border:        #000000;
        --toc-text:          #000000;
        --toc-heading:       #000000;
        --toc-border-strong: #000000;
    }

    .najibul-toc {
        border-width: 2px;
    }

    .najibul-toc-link {
        font-weight: 600;
    }

    .najibul-toc-link:focus-visible,
    .najibul-toc-toggle:focus-visible {
        outline-width: 3px;
    }
}

@media (prefers-color-scheme: dark) and (prefers-contrast: high) {
    .najibul-toc-wrapper {
        --toc-border:        #ffffff;
        --toc-text:          #ffffff;
        --toc-heading:       #ffffff;
        --toc-border-strong: #ffffff;
    }
}

/* Reduced motion preference — instant transitions */
@media (prefers-reduced-motion: reduce) {
    .najibul-toc-wrapper *,
    .najibul-toc-wrapper *::before,
    .najibul-toc-wrapper *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    .najibul-toc-toggle svg {
        transition: none !important;
    }
}


/* ═══════════════════════════════════════════════════════════════════
 * 22. EDITOR PREVIEW CONSISTENCY (scope-locked)
 * ═══════════════════════════════════════════════════════════════════ */

/* Inside the Gutenberg editor, ensure the SSR output behaves
 * predictably and doesn't accidentally inherit editor chrome */
body.block-editor-page .najibul-toc-wrapper,
body.wp-admin .editor-styles-wrapper .najibul-toc-wrapper {
    margin-block: 0;
    margin-inline: 0;
    max-inline-size: 100%;
}

body.block-editor-page .najibul-toc-wrapper .najibul-toc,
body.wp-admin .editor-styles-wrapper .najibul-toc-wrapper .najibul-toc {
    border-radius: var(--toc-radius);
}

/* Editor preview: prevent hover-lift from mimicking user interaction */
body.block-editor-page .najibul-toc-wrapper:hover,
body.wp-admin .editor-styles-wrapper .najibul-toc-wrapper:hover {
    /* keep default look */
}

} /* end @layer najibul-toc */