/* Matches gpai-abstract visual language; colors via CSS variables from settings */
.gpai-toc-container {
    --gpai-toc-accent: #2271b1;
    --gpai-toc-bg-start: #f7f9fc;
    --gpai-toc-bg-end: #f0f6fb;
    --gpai-toc-border: #d8e6f2;
    --gpai-toc-link: #1d3f5f;
    --gpai-toc-link-sub: #3d5a73;
    --gpai-toc-sublist-border: #c5d9ea;

    clear: both;
    margin: 24px 0 28px;
    padding: 18px 20px 20px;
    border-radius: 6px;
    background: linear-gradient(135deg, var(--gpai-toc-bg-start) 0%, var(--gpai-toc-bg-end) 100%);
    border: 1px solid var(--gpai-toc-border);
    border-inline-start: 4px solid var(--gpai-toc-accent);
    box-shadow: 0 1px 3px color-mix(in srgb, var(--gpai-toc-accent) 8%, transparent);
    max-width: 100%;
    font-size: 0.97em;
    line-height: 1.65;
    direction: ltr;
    text-align: start;
    unicode-bidi: isolate;
}

.gpai-toc-container[dir="rtl"] {
    direction: rtl;
    text-align: right;
}

.gpai-toc-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    margin-bottom: 14px;
    cursor: pointer;
    user-select: none;
}

.gpai-toc-container.is-collapsed .gpai-toc-header {
    margin-bottom: 0;
}

.gpai-toc-title {
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.8em;
    letter-spacing: 0.06em;
    color: var(--gpai-toc-accent);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 8px;
    text-align: inherit;
}

.gpai-toc-title::before {
    content: '';
    display: inline-block;
    width: 18px;
    height: 18px;
    flex-shrink: 0;
    background-color: var(--gpai-toc-accent);
    -webkit-mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='black'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M4 6h16M4 12h16M4 18h7'%3E%3C/path%3E%3C/svg%3E");
    mask-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='black'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M4 6h16M4 12h16M4 18h7'%3E%3C/path%3E%3C/svg%3E");
    -webkit-mask-size: contain;
    mask-size: contain;
    -webkit-mask-repeat: no-repeat;
    mask-repeat: no-repeat;
}

.gpai-toc-toggle {
    background: #fff;
    border: 1px solid var(--gpai-toc-sublist-border);
    border-radius: 4px;
    padding: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    height: 30px;
    transition: background 0.2s ease, border-color 0.2s ease;
    flex-shrink: 0;
}

.gpai-toc-toggle:hover {
    background: color-mix(in srgb, var(--gpai-toc-accent) 12%, #fff);
    border-color: var(--gpai-toc-accent);
}

.gpai-toc-toggle-icon {
    display: inline-block;
    width: 8px;
    height: 8px;
    border-inline-end: 2px solid var(--gpai-toc-accent);
    border-bottom: 2px solid var(--gpai-toc-accent);
    transform: rotate(45deg) translateY(-2px);
    transition: transform 0.25s ease;
}

.gpai-toc-container.is-collapsed .gpai-toc-toggle-icon {
    transform: rotate(-45deg) translateY(2px) translateX(1px);
}

.gpai-toc-nav {
    display: block;
    direction: inherit;
    text-align: inherit;
}

.gpai-toc-container.is-collapsed .gpai-toc-nav {
    display: none;
}

.gpai-toc-list,
.gpai-toc-sublist {
    list-style: none;
    padding: 0;
    margin: 0;
    direction: inherit;
    text-align: inherit;
}

.gpai-toc-sublist {
    margin-block-start: 6px;
    margin-block-end: 4px;
    margin-inline-start: 0;
    margin-inline-end: 0;
    padding-inline-start: 18px;
    padding-inline-end: 0;
    border-inline-start: 2px solid var(--gpai-toc-sublist-border);
}

.gpai-toc-item {
    margin: 0;
    padding: 5px 0;
    line-height: 1.5;
    text-align: inherit;
}

.gpai-toc-link {
    color: var(--gpai-toc-link);
    text-decoration: none;
    display: inline-block;
    transition: color 0.2s ease, transform 0.2s ease;
    font-weight: 500;
    text-align: inherit;
}

.gpai-toc-link:hover,
.gpai-toc-link:focus {
    color: var(--gpai-toc-accent);
    text-decoration: underline;
}

.gpai-toc-level-3 .gpai-toc-link {
    font-weight: 400;
    font-size: 0.95em;
    color: var(--gpai-toc-link-sub);
}

.gpai-toc-link.is-active {
    color: var(--gpai-toc-accent);
    font-weight: 700;
}

.gpai-toc-container[dir="ltr"] .gpai-toc-link:hover,
.gpai-toc-container[dir="ltr"] .gpai-toc-link:focus {
    transform: translateX(2px);
}

.gpai-toc-container[dir="rtl"] .gpai-toc-link:hover,
.gpai-toc-container[dir="rtl"] .gpai-toc-link:focus {
    transform: translateX(-2px);
}

/* Back to TOC Link next to headings */
.gpai-toc-heading {
    position: relative;
}

.gpai-back-to-toc {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-inline-start: 10px;
    color: var(--gpai-toc-link-sub, #3d5a73);
    opacity: 0.2;
    transition: opacity 0.2s ease, color 0.2s ease, transform 0.2s ease;
    text-decoration: none !important;
    vertical-align: baseline;
    border-bottom: none !important;
    box-shadow: none !important;
    font-size: 0.8em;
}

.gpai-toc-heading:hover .gpai-back-to-toc,
.gpai-back-to-toc:focus {
    opacity: 1;
    color: var(--gpai-toc-accent, #2271b1);
}

.gpai-back-to-toc:hover {
    transform: translateY(-2px);
}

/* Floating back button (article title or page top) — rendered in wp_footer */
.gpai-toc-floating-btn {
    position: fixed;
    bottom: 24px;
    z-index: 9999;
    box-sizing: border-box;
    width: 42px;
    height: 42px;
    min-width: 42px;
    min-height: 42px;
    max-width: 42px;
    max-height: 42px;
    padding: 0;
    margin: 0;
    border-radius: 50%;
    background-color: var(--gpai-toc-accent, #2271b1);
    color: #fff;
    border: none;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    line-height: 1;
    font: inherit;
    appearance: none;
    -webkit-appearance: none;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(16px);
    transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease, background-color 0.2s ease, box-shadow 0.2s ease;
}

.gpai-toc-floating-btn svg {
    display: block;
    flex-shrink: 0;
    pointer-events: none;
}

.gpai-toc-floating-btn--ltr {
    right: 24px;
    left: auto;
}

.gpai-toc-floating-btn--rtl {
    left: 24px;
    right: auto;
}

.gpai-toc-floating-btn.is-visible {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
}

.gpai-toc-floating-btn.is-visible:hover,
.gpai-toc-floating-btn.is-visible:focus-visible {
    background-color: color-mix(in srgb, var(--gpai-toc-accent, #2271b1) 80%, #000);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.2);
    transform: translateY(-2px);
    outline: none;
}

@media (max-width: 782px) {
    .gpai-toc-floating-btn {
        bottom: 20px;
    }

    .gpai-toc-floating-btn--ltr {
        right: 16px;
    }

    .gpai-toc-floating-btn--rtl {
        left: 16px;
    }
}