.smarttoc-pro__wrapper {
    width: 100%;
    padding: 0;
    box-sizing: border-box;
    font-family: system-ui, -apple-system, Roboto, sans-serif;
}

.smarttoc-pro__inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 16px 12px;
    background: #fff;
    border-bottom: 1px solid #e0e0e0;
}

.smarttoc-pro__heading {
    font-weight: 600;
    font-size: 18px;
    cursor: pointer;
    padding: 0 0 8px;
    color: #202124;
    display: flex;
    justify-content: space-between;
}

.smarttoc-pro__heading::after {
    content: "▾";
    font-size: 18px;
    transition: transform .25s ease;
}

.smarttoc-pro__heading[aria-expanded="true"]::after {
    transform: rotate(180deg);
}

.smarttoc-pro__dropdown {
    padding-top: 4px;
    max-height: 600px;
    overflow: auto;
    transition: max-height .28s ease, padding .2s ease;
}

.smarttoc-pro__collapsed {
    max-height: 0;
    padding-top: 0;
    overflow: hidden;
}

.smarttoc-pro__list {
    list-style: none;
    padding-left: 16px;
    border-left: 1px solid #e0e0e0;
}

.smarttoc-pro__item {
    padding: 8px 0;
}

.smarttoc-pro__link {
    text-decoration: none;
    font-size: 16px;
    color: #3c4043;
}

.smarttoc-pro__item.active .smarttoc-pro__link {
    color: #1a73e8;
    font-weight: 500;
}

@media (max-width: 768px) {
    .smarttoc-pro__inner { padding: 14px 12px; }
    .smarttoc-pro__heading { font-size: 16px; }
    .smarttoc-pro__link { font-size: 15px; }
}