.aiosc_toc_wrapper {
    border: 2px solid #f2f2f2;
    padding: 10px 25px 1px 25px;
    margin: 35px 0;
    background: #fbfbfb;
}

.aiosc_toc_checkbox {
    display: none;
}

.aiosc_toc_title {
    font-weight: bold;
    font-size: 1.1em;
    cursor: pointer;
    user-select: none;
    display: block;
    margin-bottom: 10px;
    position: relative;
    padding-right: 20px;
}

/* Arrow indicator */
.aiosc_toc_title::after {
    content: "▼";
    position: absolute;
    right: 0;
    top: 0;
    font-size: 0.9em;
    transition: transform 0.3s ease;
    transform-origin: center;
}

/* Rotate arrow when checked */
.aiosc_toc_checkbox:checked + .aiosc_toc_title::after {
    transform: rotate(-180deg);
}

/* Hide TOC list by default */
.aiosc_toc_list {
    list-style: none;
    padding-left: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
    margin: 0 !important;
}

/* Show TOC list when checked */
.aiosc_toc_checkbox:checked + .aiosc_toc_title + .aiosc_toc_list {
    max-height: 5000px; /* large enough to show all */
    margin-top: 0.5em;
    border-top: 2px solid #f2f2f2;
    padding-top: 10px;
    padding-bottom: 20px;
}

.aiosc_toc_item {
    margin: 6px 0;
}

.aiosc_toc_list .aiosc_level_3 a {
    margin-left: 15px;
    font-size: 0.95em;
}

.aiosc_toc_wrapper .aiosc_toc_list a {
    text-decoration: none;
}

.aiosc_toc_wrapper .aiosc_toc_list .aiosc_level_2 a {
    font-weight: 500;
}

.aiosc_toc_wrapper .aiosc_toc_list .aiosc_level_3 a {
    font-weight: 400;
}